pneumatic tires

Abstract

To provide a pneumatic tire which improves mud traction performance and cut resistance performance while suppressing increase of tire mass.SOLUTION: A pneumatic tire is given in which a plurality of protectors 10 are formed. The protector 10 includes: a first protector 11; and a second protector 12 adjacent thereto through a groove-like part 13. A tie-bar 15 is formed in the groove-like part 13 to connect the first protector 11 with the second protector 12. The tie-bar 15 is formed partially in a tire radial direction area of the groove-like part 13. A protrusion height of the tie-bar 15 is smaller than protrusion heights of the first protector 11 and the second protector 12. Each of the first protector 11 and the second protector 12 includes: an inside part 20; and an outside part 21 that is positioned at the outer side in the tire radial direction relative to the inside part 20. A maximum length of the inside part 20 in a tire circumferential direction is larger than a maximum length of the outside part 21 in the tire circumferential direction. The tie-bar 15 is connected with the inside part 20 and not connected with the outside part 21.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to pneumatic tires. [Background technology]

[0002] Patent Document 1 below describes a pneumatic tire having a plurality of side grooves and a plurality of side blocks defined by the side grooves in the side region. The pneumatic tire of Patent Document 1 is said to have improved running performance and cut resistance on unpaved roads, including muddy areas. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-44882 Summary of the Invention [Problem to be solved by the invention]

[0004] Pneumatic tires for running on rough terrain such as muddy ground are provided with multiple protectors on the sidewalls to improve the cut resistance and mud performance of the sidewalls, but such protectors have the problem of increasing the tire mass.

[0005] The present disclosure has been devised in consideration of the above problems, and has as its main object to provide a pneumatic tire that can improve mud traction performance and cut resistance while suppressing an increase in tire mass. [Means for solving the problem]

[0006] The present disclosure relates to a pneumatic tire comprising a first buttress portion extending radially inward from a first tread edge, the first buttress portion having a plurality of protectors formed therein that protrude axially outward from the tire, the protectors comprising a first protector and a second protector adjacent to the first protector via a groove portion extending radially between the first protector and the second protector, a tie bar formed in the groove portion that connects the first protector and the second protector, the tie bar being formed partially in a radial region of the groove portion, and having a raised height that is smaller than the raised heights of the first protector and the second protector. [Effects of the Invention]

[0007] By employing the above-described configuration, the pneumatic tire of the present disclosure can improve mud traction performance and cut resistance while suppressing an increase in tire mass. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a tire meridian cross-sectional view showing an embodiment of a pneumatic tire of the present disclosure. [Figure 2] FIG. 2 is a perspective view of a first buttress portion. [Figure 3] FIG. 2 is a front view of the first buttress portion. [Figure 4] FIG. 4 is an enlarged view of FIG. [Figure 5] FIG. 4 is an enlarged view of FIG. [Figure 6] FIG. 4 is an enlarged view of FIG. [Figure 7] FIG. 7 is a cross-sectional view taken along line AA in FIG. 6. [Figure 8] FIG. 2 is a front view of the first buttress portion. [Figure 9] 10A is a front view of another embodiment of a protector pair, FIG. 10B is a cross-sectional view taken along line BB in FIG. 10A, and FIG. 10C is a cross-sectional view taken along line BB in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. FIG. 1 is a tire meridian cross-sectional view including the tire rotation axis (not shown) of a pneumatic tire (hereinafter sometimes simply referred to as "tire") 1 of this embodiment in a normal state. FIG. 1 shows a pneumatic tire mounted on a 4WD vehicle or the like that can travel on rough terrain, as a preferred embodiment. However, it goes without saying that the present disclosure can also be applied to tires 1 for light trucks and heavy load vehicles.

[0010] The "normal state" refers to a state in which the tire 1 is mounted on a normal rim (not shown), inflated to a normal internal pressure, and no load is applied. In this specification, unless otherwise specified, the dimensions of each part of the tire 1 are values ​​measured in this normal state.

[0011] A "genuine rim" is a rim that is defined for each tire by a standard system that includes the standard on which tire 1 is based, such as a "standard rim" for JATMA, a "design rim" for TRA, or a "measuring rim" for ETRTO.

[0012] "Normal internal pressure" is the air pressure specified for each tire by each standard in the standard system, including the standard on which tire 1 is based. In the case of JATMA, it is the "maximum air pressure," in the case of TRA, it is the maximum value listed in the table "TIRE LOAD LIMITS SAT VARIOUSCOLD INFLATION PRESSURES," and in the case of ETRTO, it is the "INFLATION PRESSURE."

[0013] The tire 1 of this embodiment contains ties and other components such as a carcass 6 and a belt layer 7. Known embodiments are appropriately adopted for these tire components.

[0014] In this embodiment, the tire 1 includes a first buttress portion 4A extending radially inward from the first tread edge To. The tire 1 also includes, for example, a second buttress portion 4B extending radially inward from the second tread edge Ti. The second buttress portion 4B is formed in the same manner as the first buttress portion 4A, and therefore a description thereof will be omitted. Note that the second buttress portion 4B may be formed in a manner different from that of the first buttress portion 4A.

[0015] The first tread edge To and the second tread edge Ti are defined as the outermost contact points in the tire axial direction when the tire 1 in a normal state is placed on a flat surface with a normal load and a camber angle of 0 degrees. A tread portion 2 is formed between the first tread edge To and the second tread edge Ti.

[0016] The "normal load" is the load specified for each tire by the standard, and is the maximum load capacity in the case of JATMA, the maximum value listed in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" in the case of TRA, and "LOAD CAPACITY" in the case of ETRTO.

[0017] Fig. 2 is a perspective view of the first buttress portion 4A. Fig. 3 is a front view of the first buttress portion 4A. As shown in Figs. 1 to 3, the first buttress portion 4A of this embodiment is formed with a plurality of protectors 10 that protrude outward in the axial direction of the tire. The protectors 10 include a first protector 11 and a second protector 12 adjacent to the first protector 11 with a groove-shaped portion 13 interposed between them and extending in the radial direction of the tire.

[0018] A tie bar 15 is formed in the groove portion 13 to connect the first protector 11 and the second protector 12. Such tie bar 15 increases the circumferential rigidity of the first protector 11 and the second protector 12, and increases the cut resistance of the first buttress portion 4A as well as the chipping resistance of the protector 10. In addition, the tie bar 15 increases the rigidity of the first protector 11 and the second protector 12, thereby increasing the shear force on muddy roads when the protector 10 is used, improving mud traction performance.

[0019] The tie bars 15 are formed partially in the tire radial region 13R of the groove-shaped portion 13. The tie bars 15 have a raised height h2 (shown in FIG. 7) that is smaller than the raised height h1 of the first protector 11 and the second protector 12. Such tie bars 15 can suppress an increase in tire mass.

[0020] The first buttress portion 4A is provided with a recess 16 recessed axially inward in the tire direction. In this embodiment, the recess 16 extends continuously in the tire circumferential direction. Although not particularly limited, the width w1 of the recess 16 in the tire radial direction is 1.0 to 3.0 mm. The depth d1 (shown in FIG. 7) of the recess 16 is 0.5 to 2.0 mm. Such recess 16 adds variety to the appearance of the first buttress portion 4A and improves the appearance performance. The depth d1 of the recess 16 is the depth from the outward surface 8A of the shoulder block 8R, which will be described later.

[0021] In this embodiment, the protector 10 is disposed radially inward of the recess 16. The protector 10 is formed, for example, only by a plurality of protector pairs 10A each consisting of a first protector 11 and a second protector 12. Note that the protector 10 is not limited to this form, and may include a third protector (not shown) having a shape different from the first protector 11 and the second protector 12.

[0022] Each of the first protector 11 and the second protector 12 includes an inner portion 20 and an outer portion 21 located radially outward of the inner portion 20. The inner portion 20 and the outer portion 21 are separated by a tire circumferential line n passing through an intersection T between an outer edge portion 36 and an intermediate edge portion 38 (described later) (shown in FIG. 5).

[0023] The maximum length Wa of the inner portion 20 in the tire circumferential direction is greater than the maximum length Wb of the outer portion 21 in the tire circumferential direction. Such an inner portion 20 increases the rigidity of the outer portion 21, which is likely to come into contact with mud, etc., thereby further improving mud traction performance and cut resistance. It also improves the appearance of the protector 10.

[0024] In each protector 10, the maximum length Wb of the outer portion 21 is preferably 50% or more of the maximum length Wa of the inner portion 20, more preferably 60% or more, and more preferably 80% or less, and even more preferably 70% or less. This allows the above-mentioned effects to be effectively achieved. In this embodiment, the maximum length Wa of the inner portion 20 is 23.9 to 33.9 mm.

[0025] In a front view of the first buttress portion 4A, the first protector 11 has an L-shape in which its inner portion 20A protrudes relative to the outer portion 21A on the side opposite the groove portion 13 in the tire circumferential direction. The second protector 12 has an inverted L-shape in which its inner portion 20B protrudes relative to the outer portion 21B on the side opposite the groove portion 13 in the tire circumferential direction. In other words, each of the first protector 11 and the second protector 12 has an open region K at the position where the inner portion 20 and the outer portion 21 connect, which is open on the side opposite the groove portion 13 in the tire circumferential direction and toward the outside in the tire radial direction. Shear force against mud and the like is also exerted in this open region K, improving mud traction performance. In this specification, the terms "L-shape" and "inverted L-shape" refer to an angle α1 between a line P1 connecting both ends of an inner peripheral edge 30 (described later) and a line P2 connecting both ends of an inward edge 32 (shown in Figure 4), and an angle α2 between a line P3 connecting both ends of an outer edge 36 (described later) and a line P4 connecting both ends of an intermediate edge 38 (shown in Figure 5), which are 80 to 120 degrees.

[0026] 2, each of the first protector 11 and the second protector 12 includes a side surface 25 rising from the outer surface 4s of the first buttress portion 4A and an outer surface 26 connecting the axially outer ends 25e of the side surfaces 25. In this specification, the outer surface 4s refers to a surface that, in a normal state, extends smoothly except for localized irregularities including raised marks such as emblems and textured patterns. In this embodiment, the outer surface 4s forms the groove bottom 13s of the groove portion 13.

[0027] FIG. 4 is an enlarged view of FIG. 3. As shown in FIG. 4, the outer end 25e of the side surface 25 forms a side edge 28 where the side surface 25 and the outer surface 26 intersect. In this embodiment, each of the side edges 28 of the first protector 11 and the second protector 12 includes an inner peripheral edge 30, an outer peripheral edge 31, an inward edge 32, and an outward edge 33. The inner peripheral edge 30 extends in the tire circumferential direction, for example, on the innermost side of each protector 11, 12 in the tire radial direction. The outer peripheral edge 31 extends in the tire circumferential direction on the outermost side of each protector 11, 12 in the tire radial direction. The inward edge 32 connects the first end 30e of the inner peripheral edge 30 and the first end 31e of the outer peripheral edge 31 and is adjacent to the groove portion 13. The outward edge 33 connects the second end 30i of the inner peripheral edge 30 and the second end 31i of the outer peripheral edge 31 to form an open region K.

[0028] The inner circumferential edge 30A of the first protector 11 and the inner circumferential edge 30B of the second protector 12 extend to form a single imaginary line X, which in this embodiment is an arc-shaped imaginary line X. Such inner circumferential edges 30A, 30B suppress a decrease in shear force when traveling on muddy ground, thereby improving mud traction performance. In this specification, "forming a single imaginary line" not only means that the inner circumferential edges 30A, 30B are located on a single straight line or an arc of a single radius of curvature, but also includes a case where the maximum distance (not shown) between the imaginary line X and each inner circumferential edge 30A, 30B is 2 mm or less. In this embodiment, the imaginary line X is inclined with respect to the tire circumferential direction. Note that the imaginary line X includes straight lines and arc-shaped lines, but does not include broken lines or wavy lines.

[0029] The outer peripheral edge 31 of each of the first protector 11 and the second protector 12 forms, for example, a recess 16. In this embodiment, the outer peripheral edge 31 of each of the first protector 11 and the second protector 12 is formed on the tire circumferential line n.

[0030] FIG. 5 is an enlarged view of FIG. 3. As shown in FIG. 5, the inward edge 32A of the first protector 11 includes a first edge 34 and a second edge 35. The first edge 34 extends linearly from the first end 31e of the outer peripheral edge 31 toward the tire radially inward direction. The second edge 35 is continuous with the first edge 34 and is inclined at a larger angle relative to the tire radial direction than the first edge 34. Although not particularly limited, the angle α3 between the first edge 34 and the second edge 35 is an obtuse angle. Such an inward edge 32A increases the groove width of the grooved portion 13 on the radially inner side of the tire. The angle α3 is preferably 100 to 130 degrees. The inward edge 32B of the second protector 12 extends linearly in the tire radial direction.

[0031] In this embodiment, the first edge 34 of the first protector 11 and the inward edge 32B of the second protector 12 extend parallel to each other. This reduces the difference in rigidity between the first protector 11 and the second protector 12, allowing them to exert a high shear force against mud, etc. In this specification, the term "parallel" means that the difference in angle between them relative to the tire radial direction is not only 0 degrees, but also within 5 degrees.

[0032] Each outward edge 33 includes an outer edge 36 extending from the outer peripheral edge 31, an inner edge 37 extending from the inner peripheral edge 30, and an intermediate edge 38 connecting the outer edge 36 and the inner edge 37. The outer edge 36, the inner edge 37, and the intermediate edge 38 extend, for example, linearly. In each outward edge 33, in this embodiment, an open region K is formed by the outer edge 36 and the intermediate edge 38. In each protector 11, 12, the intermediate edge 38 is inclined radially inward toward the opposite side of the tire circumferential direction from the groove-shaped portion 13. This increases the volume of mud and the like that can be dug up by the intermediate edge 38 and the outer edge 36, thereby improving mud traction performance and cut resistance.

[0033] Fig. 6 is an enlarged view of Fig. 3. As shown in Fig. 6, the tie bar 15 is connected to the inner portion 20. The tie bar 15 is connected, for example, to the inner portion 20A of the first protector 11 and the inner portion 20B of the second protector 12. Such tie bar 15 increases the rigidity of the inner portion 20, thereby improving cut resistance and mud traction performance. In addition, the tie bar 15 is not connected to the outer portion 21. As a result, the outer portion 21, which has a relatively low rigidity, maintains its deformation due to rotation of the tire 1, so that mud and the like in the groove portion 13 sandwiched between the outer portions 21 is smoothly discharged.

[0034] The tie bar 15 includes, for example, an inner edge 15A and an outer edge 15B. The inner edge 15A and the outer edge 15B extend in the tire circumferential direction. In this embodiment, the inner edge 15A is connected to a position 40 where the first edge portion 34 and the second edge portion 35 are connected. The outer edge 15B is disposed further outward in the tire radial direction than the inner edge 15A. The inner edge 15A and the outer edge 15B extend, for example, in parallel. In this embodiment, the inner edge 15A and the outer edge 15B extend parallel to the imaginary line X.

[0035] The length L1 of the tie bar 15 in the tire radial direction is preferably 50% or less of the length La of the groove portion 13 in the tire radial direction. This prevents a decrease in the volume of the groove portion 13, thereby suppressing an increase in tire mass. To suppress an increase in tire mass while improving mud traction performance and cut resistance, the length L1 of the tie bar 15 is preferably 20% or more of the length La of the groove portion 13, more preferably 22% or more, even more preferably 30% or less, and still more preferably 28% or less. In this specification, the length L1 of the groove portion 13 is the greater of the lengths in the tire radial direction of the inboard edges 32A, 32B that form the groove portion 13.

[0036] Fig. 7 is a cross-sectional view taken along line AA in Fig. 6. As shown in Fig. 7, the difference (h1a-h2) between the raised height h1a of the first protector 11 and the raised height h2 of the tie bar 15, and the difference (h1b-h2) between the raised height h1b of the second protector 12 and the raised height h2 of the tie bar 15 are both preferably 0.5 mm or more. This effectively suppresses an increase in tire mass. To improve mud traction performance and cut resistance, the difference (h1a-h2) and the difference (h1b-h2) are both more preferably 1.0 mm or more, more preferably 2 mm or less, and even more preferably 1.5 mm or less.

[0037] The protruding height h1a of the first protector 11 and the protruding height h1b of the second protector 12 are both preferably 1.0 mm or more, more preferably 1.5 mm or more, and are preferably 5.0 mm or less, and more preferably 4.0 mm or less.

[0038] In this embodiment, the raised height h1a of the first protector 11 and the raised height h1b of the second protector 12 are the same. The raised height h1a of the first protector 11 and the raised height h1b of the second protector 12 may be different.

[0039] 1 and 2, the tread portion 2 has a shoulder land portion 8 on the axially inner side of the first tread edge To. The shoulder land portion 8 is divided into a plurality of shoulder blocks 8R by a plurality of shoulder lateral grooves 9 connected to the first tread edge To.

[0040] FIG. 8 is a front view of the first buttress portion 4A. As shown in FIG. 8, in this embodiment, the shoulder block 8R has an outward surface 8A that extends axially inward from the first tread edge To to form the first buttress portion 4A. The outward surface 8A includes, for example, a pair of block edges 39 that are spaced apart in the tire circumferential direction and extend in the tire radial direction. Each block edge 39 connects the first tread edge To and the recess 16 and extends linearly. Each block edge 39 includes a first block edge 39a that forms a shoulder lateral groove 9 and a second block edge 39b that is inclined more sharply with respect to the tire radial direction than the first block edge 39a. The second block edge 39b is inclined, for example, radially inward toward the first block edge 39a.

[0041] In this embodiment, the shoulder lateral grooves 9 extend axially outward from the first tread edge To. In other words, the shoulder lateral grooves 9 also extend into the first buttress portion 4A. As a result, a pair of groove edges 9a, 9a extending in the longitudinal direction of the shoulder lateral grooves 9 are formed in the first buttress portion 4A. In this embodiment, each groove edge 9a extends linearly. Each groove edge 9a is connected to, for example, a recess 16.

[0042] The groove-like portions 13 are arranged at positions that at least partially overlap with a projected area R1, which is a projection of the shoulder lateral grooves 9 inward in the tire radial direction. The projected area R1 is an area surrounded by a pair of extension lines 9e that extend each groove edge 9a inward in the tire radial direction. In Figure 8, the projected area R1 is indicated by hatching. In this embodiment, the groove-like portions 13 are arranged at positions that entirely overlap with the projected area R1.

[0043] The width Wg of the groove-like portion 13 is preferably 90% or more of the groove width Ws of the shoulder lateral groove 9, more preferably 95% or more, and preferably 110% or less, and even more preferably 105% or less. Since the width Wg of the groove-like portion 13 is 90% or more of the groove width Ws of the shoulder lateral groove 9, mud traction performance can be improved. Since the width Wg of the groove-like portion 13 is 110% or less of the groove width Ws of the shoulder lateral groove 9, high cut resistance can be maintained. The width Wg of the groove-like portion 13 is preferably 20% to 40% of the maximum length Wa (shown in FIG. 3) of the inner portion 20, for example. Furthermore, the groove width Ws of the shoulder lateral groove 9 is preferably 3.7 to 9.7 mm.

[0044] The outer portion 21 is positioned so as to at least partially overlap a projected area R2, which is a projection of the shoulder block 8R radially inward in the tire direction. The projected area R2 is an area surrounded by a pair of radial lines s1 passing through the inner ends 39i of each block edge 39 of the shoulder block 8R. In FIG. 8, the projected area R2 is indicated by hatching. In this embodiment, the entire outer portion 21 is positioned so as to overlap the projected area R2. More specifically, the entire outer portion 21 of the first protector 11 and the entire outer portion 21 of the second protector 12 are positioned so as to overlap the respective projected areas R2. This increases the apparent rigidity of the protector 10 and the shoulder block 8R, further improving mud traction performance.

[0045] FIG. 9(a) is a front view of a protector pair 10A of another embodiment. FIG. 9(b) is a cross-sectional view taken along line BB in FIG. 9(a). The same components as those of the protector pair 10A of this embodiment are designated by the same reference numerals, and their description may be omitted. As shown in FIGS. 9(a) and 9(b), in this embodiment, the inner portion 20 is provided with a rim 40 extending along the side surface 25 (side edge 28) on the outer surface 26. In this embodiment, the rim 40 is formed as a rib 40R protruding from the outer surface 26. Such a rim 40 adds variation to the visibility of the protector 10, improving its appearance. It is preferable that the rim 40 be provided on each of the inner portions 20 of the first protector 11 and the second protector 12. It is also preferable that the rim 40 not be formed on the outer portion 21. Furthermore, the edging portion 40 may be formed, for example, by two ribs 40R extending along the side surface 25 (not shown).

[0046] Figure 9(c) is a cross-sectional view of another embodiment taken along line BB in Figure 9(a). The same components as those in the protector pair 10A of this embodiment are given the same reference numerals, and their description may be omitted. As shown in Figure 9(c), the edging 40 of this embodiment is formed as a groove-shaped body 40G recessed from the outer surface 26. This edging 40 also adds a change to the visibility of the protector 10, improving its appearance.

[0047] Although particularly preferred embodiments of the present disclosure have been described in detail above, the present disclosure is not limited to the illustrated embodiments and can be modified and implemented in various forms. [Example]

[0048] Tires were manufactured with the basic structure shown in Figure 1 and the buttress portion shown in Figure 2, and their mud traction performance, cut resistance, tire mass, and appearance were evaluated. The test methods and common specifications are as follows: Tire size: 265 / 65R18 Rim: 8.0J Internal pressure: 230kPa In each example, Wg and wa are the same.

[0049] <Mud traction performance> Each test tire was mounted on all wheels of a 3500cc four-wheel drive vehicle. A test driver then drove the vehicle on a test course with a muddy road surface, and the driving characteristics related to traction were evaluated by the test driver's senses. The results are shown on a scale with Comparative Example 1 being 100. The higher the score, the greater the traction and the better the mud performance.

[0050] <Cut resistance> Using the above vehicle, a test driver drove approximately 1,500 km over a rocky road containing rocks and rubble, and then sensory evaluation of cut resistance was performed based on the depth and length of cuts that appeared on the outer surface of the buttress. The results are shown on a scale where Comparative Example 1 is rated as 100. The higher the score, the smaller the cuts and the better the cut resistance.

[0051] <Tire mass> The mass of the first buttress portion of each test tire was measured. The results are expressed as an index, with the reciprocal of the mass (kg) of Comparative Example 1 set to 100. The larger the value, the smaller the mass, and the better the result. Note that tires with smaller masses have better rolling resistance performance.

[0052] <Appearance performance> Ten test drivers sensorily evaluated the beauty and visibility of the first buttress portion. The results are shown as a score (average score of the 10 drivers) with Comparative Example 1 being 100. The higher the score, the better the appearance performance. The test results are shown in Table 1. Any sample tire with a cut resistance, mud performance, or tire mass of 95 or less was deemed to have failed the test. The edging of Example 15 was as shown in Figure 9(b).

[0053] [Table 1]

[0054] [Table 2]

[0055] As a result of the test, it was confirmed that the tires of the examples had improved cut resistance and mud performance compared to the conventional tires. It was also confirmed that the increase in tire mass was suppressed for the tires of the examples.

[0056] [Note] The present disclosure includes the following aspects.

[0057] [Disclosure 1] A pneumatic tire, a first buttress portion extending radially inward from the first tread edge, The first buttress portion is formed with a plurality of protectors that protrude axially outward from the tire, the protector includes a first protector and a second protector adjacent to the first protector with a groove-like portion extending in the tire radial direction interposed therebetween, a tie bar connecting the first protector and the second protector is formed in the groove portion, The tie bar is partially formed in a radial region of the groove portion, The tie bar has a raised height that is smaller than the raised heights of the first protector and the second protector. Pneumatic tires. [Disclosure 2] The pneumatic tire according to Disclosure 1, wherein the length of the tie bar in the tire radial direction is 50% or less of the length of the groove portion in the tire radial direction. [Disclosure 3] A pneumatic tire described in Disclosure 1 or 2, wherein the difference (h1a-h2) between the raised height h1a of the first protector and the raised height h2 of the tie bar, and the difference (h1b-h2) between the raised height h1b of the second protector and the raised height h2 of the tie bar are both 0.5 mm or more. [Disclosure 4] The pneumatic tire according to any one of Disclosures 1 to 3, wherein the raised height h1a of the first protector and the raised height h1b of the second protector are both 1.0 to 5.0 mm. [Disclosure 5] A shoulder land portion is provided in the tread portion from the first tread end to the inside in the tire axial direction, The shoulder land portion is divided into a plurality of shoulder blocks by a plurality of shoulder lateral grooves connected to the first tread edge, The pneumatic tire according to any one of Disclosures 1 to 4, wherein the groove-shaped portion is disposed at a position that at least partially overlaps with a projected area of ​​the shoulder lateral groove projected radially inwardly in the tire. [Disclosure 6] The pneumatic tire according to Disclosure 5, wherein the width of the groove portion is 90% to 110% of the groove width of the shoulder lateral groove. [Disclosure 7] each of the first protector and the second protector includes an inner portion and an outer portion located radially outward of the inner portion; The pneumatic tire according to any one of Disclosures 1 to 6, wherein the maximum length of the inner portion in the tire circumferential direction is greater than the maximum length of the outer portion in the tire circumferential direction. [Disclosure 8] The pneumatic tire of Disclosure 7, wherein the tie bar is connected to the inner portion. [Disclosure 9] In a front view of the first buttress portion, the inner portion of the first protector has an L-shape that protrudes toward the opposite side of the groove portion relative to the outer portion in the tire circumferential direction, The pneumatic tire according to Disclosure 7 or 8, wherein the inner portion of the second protector has an inverted L shape that protrudes in the tire circumferential direction on the opposite side to the groove portion relative to the outer portion. [Disclosure 10] each of the first protector and the second protector includes a side surface rising from an outer surface of the first buttress portion and an outer surface connecting outer ends of the side surfaces in the tire axial direction, The pneumatic tire according to any one of Disclosures 7 to 9, wherein the inner portion is provided with a edging portion extending along the side surface on the outer surface. [Explanation of symbols]

[0058] 1 pneumatic tire 10 Protector 11 First Protector 12 Second protector 13 Groove 13R Tire radial area 15 Tie bar

Claims

1. A pneumatic tire, a first buttress portion extending radially inward from the first tread edge, The first buttress portion is formed with a plurality of protectors that protrude axially outward from the tire, the protector includes a first protector and a second protector adjacent to the first protector with a groove-like portion extending in the tire radial direction interposed therebetween, a tie bar connecting the first protector and the second protector is formed in the groove portion, The tie bar is partially formed in a radial region of the groove portion, the tie bar has a raised height that is smaller than the raised heights of the first protector and the second protector; each of the first protector and the second protector includes an inner portion and an outer portion located radially outward of the inner portion; a maximum length of the inner portion in the tire circumferential direction is greater than a maximum length of the outer portion in the tire circumferential direction, the tie bar is connected to the inner portion; the tie bar is not connected to the outer portion; Pneumatic tires.

2. A pneumatic tire, a first buttress portion extending radially inward from the first tread edge, The first buttress portion is formed with a plurality of protectors that protrude axially outward from the tire, the protector includes a first protector and a second protector adjacent to the first protector with a groove-like portion extending in the tire radial direction interposed therebetween, a tie bar connecting the first protector and the second protector is formed in the groove portion, The tie bar is partially formed in a radial region of the groove portion, the tie bar has a raised height that is smaller than the raised heights of the first protector and the second protector; each of the first protector and the second protector includes an inner portion and an outer portion located radially outward of the inner portion; a maximum length of the inner portion in the tire circumferential direction is greater than a maximum length of the outer portion in the tire circumferential direction, each of the first protector and the second protector includes a side surface rising from an outer surface of the first buttress portion and an outer surface intersecting the side surface at a side edge that is an outer end of the side surface in the tire axial direction, the inner portion is provided with a rim extending over the outer surface; The edging portion extends along the side edge and is spaced apart from the side edge. Pneumatic tires.

3. A pneumatic tire, a first buttress portion extending radially inward from the first tread edge, The first buttress portion is formed with a plurality of protectors that protrude axially outward from the tire, the protector includes a first protector and a second protector adjacent to the first protector with a groove-like portion extending in the tire radial direction interposed therebetween, a tie bar connecting the first protector and the second protector is formed in the groove portion, The tie bar is partially formed in a radial region of the groove portion, the tie bar has a raised height that is smaller than the raised heights of the first protector and the second protector; each of the first protector and the second protector includes an inner portion and an outer portion located radially outward of the inner portion; a maximum length of the inner portion in the tire circumferential direction is greater than a maximum length of the outer portion in the tire circumferential direction, each of the first protector and the second protector includes a side surface rising from an outer surface of the first buttress portion and an outer surface intersecting the side surface at a side edge that is an outer end of the side surface in the tire axial direction, the inner portion is provided with a rim extending over the outer surface; The edging portion is a groove-shaped body recessed from the outer surface. Pneumatic tires.

4. A pneumatic tire, a first buttress portion extending radially inward from the first tread edge, The first buttress portion is formed with a plurality of protectors that protrude axially outward from the tire, the protector includes a first protector and a second protector adjacent to the first protector with a groove-like portion extending in the tire radial direction interposed therebetween, a tie bar connecting the first protector and the second protector is formed in the groove portion, The tie bar is partially formed in a radial region of the groove portion, the tie bar has a raised height that is smaller than the raised heights of the first protector and the second protector; each of the first protector and the second protector includes an inner portion and an outer portion located radially outward of the inner portion; a maximum length of the inner portion in the tire circumferential direction is greater than a maximum length of the outer portion in the tire circumferential direction, each of the first protector and the second protector includes a side surface rising from an outer surface of the first buttress portion and an outer surface intersecting the side surface at a side edge that is an outer end of the side surface in the tire axial direction, the inner portion is provided with a rim extending over the outer surface; The edging is not formed on the outer portion. Pneumatic tires.

5. The pneumatic tire according to claim 1 , wherein the length of the tie bar in the tire radial direction is 50% or less of the length of the groove portion in the tire radial direction.

6. 6. The pneumatic tire according to claim 1, wherein a difference (h1a-h2) between the raised height h1a of the first protector and the raised height h2 of the tie bar, and a difference (h1b-h2) between the raised height h1b of the second protector and the raised height h2 of the tie bar are both 0.5 mm or more.

7. 7. The pneumatic tire according to claim 1, wherein a raised height h1a of the first protector and a raised height h1b of the second protector are both 1.0 to 5.0 mm.

8. A shoulder land portion is provided in the tread portion axially inward from the first tread end, the shoulder land portion is divided into a plurality of shoulder blocks by a plurality of shoulder lateral grooves connected to the first tread edge, The pneumatic tire according to claim 1 , wherein the groove-like portion is disposed at a position at which at least a part of the groove-like portion overlaps with a projected area of ​​the shoulder lateral groove projected radially inwardly in the tire.

9. The pneumatic tire according to claim 8, wherein the width of the groove portion is 90% to 110% of the groove width of the shoulder lateral groove.

10. The pneumatic tire of claim 2 , wherein the tie bar is connected to the inner portion.

11. each of the first protector and the second protector includes a side surface rising from an outer surface of the first buttress portion and an outer surface connecting outer ends of the side surfaces in the tire axial direction, The pneumatic tire of claim 1 , wherein the inner portion is provided with a edging extending along the side on the outer surface.

Images