pneumatic tires

Abstract

Pneumatic tires (1), comprising: a central main groove (5) which is formed in a central zone of a tread area (2) in a tire width direction (TW) and extends in a tire circumferential direction (TC); a shoulder main groove (6, 6A, 6B) which is formed in the tread area (2) on one side of the ground contact end (GE, GE1, GE2) with respect to the central main groove (5) and extends in the tire circumferential direction (TC); a plurality of shoulder lateral grooves (8, 8A, 8B) extending in the tire width direction (TW), each shoulder lateral groove (8, 8A, 8B) having one end that communicates with the main shoulder groove (6, 6A, 6B) and another end that terminates outside a ground contact end (GE, GE1, GE2) in the tire width direction (TW), and wherein the shoulder lateral grooves (8, 8A, 8B) are spaced apart from each other in the tire circumferential direction (TC); and a shoulder block (9, 9A, 9B) bounded by the main shoulder groove (6, 6A, 6B) and two of the shoulder lateral grooves (8, 8A, 8B) adjacent to each other in the circumferential direction (TC), wherein The shoulder block (9, 9A, 9B) contains: the tread area (2), arranged inside the ground contact end (GE, GE1, GE2) in the tire width direction (TW), a side area (3) which is arranged outside the ground contact end (GE, GE1, GE2) in the tire width direction (TW) and extends in a tire radial direction, and a shoulder area (4) which is a curved area and connects the tread area (2) and the side area (3), a smooth zone (4a) which does not contain any depressions or protrusions, is provided in the shoulder block (9, 9A, 9B) in both lateral areas of the shoulder area (4) except for a central area of ​​the shoulder area (4) in the tire circumferential direction (TC), and a first lamellar slot (23) which reaches the smooth zone (4a) in the tire radial direction is provided in the side area (3), wherein the pneumatic tire (1) further comprises a second lamellar slot (22) which is arranged in the tread area (2) of the shoulder block, extends in the tire width direction (TW) and has one end that is connected to the main shoulder groove (6, 6A, 6B) and another end that reaches the smooth zone (4a), wherein the first louver slot (23) is provided at a point on an imaginary extension of the second louver slot (22), and the second lamellar slit (22) has a linear lamellar slit area (22a) connected to the main shoulder groove (6, 6A, 6B) and a wavy lamellar slit area (22b) extending to the smooth zone (4a).

Description

Technical field

[0001] The present invention relates to a pneumatic tire. Technical background

[0002] DE 697 06 334 T2 discloses a tire with a tread base compound and a tread surface compound that have synergistic properties, an extra-wide center rib, stiff shoulder lugs, and lateral grooves between the shoulder lugs that do not vary significantly in width. It has a superior combination of rolling resistance, traction, noise, and wear characteristics. The tire's RSAT value can also be fine-tuned by chamfering the edges of the lugs.

[0003] A pneumatic tire comprises a tread area, which is the primary contact zone with the ground; a sidewall area, which is a non-contact zone within the tire's sidewall; and a shoulder area, which connects the tread and sidewall areas. Specifically, the shoulder area is a curved section that seamlessly joins the tread and sidewall areas. Due to its curved shape, the shoulder area concentrates any force acting on the tire. Consequently, the shoulder area must exhibit high stiffness.

[0004] JP 6 104 215 B2 discloses a pneumatic tire that increases the stiffness of a shoulder block by improving the shape of a lamellar slot formed in a shoulder block (a shoulder connection area) that includes a tread area, a sidewall area, and a shoulder area. More precisely, a first shoulder lamellar slot and a second shoulder lamellar slot formed in the tread area of ​​the shoulder block are spaced apart in the tire width direction to increase the stiffness of the tread area of ​​the shoulder block compared to an arrangement in which a single long lamellar slot is provided. Summary of the invention; Technical task

[0005] The pneumatic tire disclosed in JP 6 104 215 B2 increases the stiffness of the tread area in a manner described above, but does not consider an improvement in the stiffness of the shoulder area, which requires high stiffness.

[0006] One object of the present invention is to increase the stiffness of a shoulder area of ​​an air tire. Solution to the task

[0007] The present invention provides a pneumatic tire as defined in claim 1.

[0008] According to this arrangement, the shoulder area of ​​the shoulder block contains the smooth zone. In this case, the stiffness of the shoulder area can be increased compared to the stiffness of a shoulder area containing a lamellar slot. Specifically, the smooth zone is provided in both lateral areas of the shoulder area, except for the central area, in the tire's circumferential direction. Accordingly, the stiffness of both end areas of the shoulder block can be increased in the tire's circumferential direction. From the perspective of steering stability, durability, and other aspects, it is preferable for one end area of ​​the shoulder block to have higher stiffness than that of the central area. Therefore, an arrangement that increases the stiffness of both end areas of the shoulder block, such as the arrangement described above, is an effective arrangement.Furthermore, since the lateral region is located outside a ground contact area, it does not need to exhibit a high stiffness equivalent to that of the shoulder region. An excessive increase in the stiffness of the lateral region is therefore avoided by the presence of the first lamellar slot provided in the lateral region. Accordingly, the stiffness of the shoulder region can be appropriately increased without an excessive increase in the stiffness of the lateral region of the shoulder block.

[0009] The first louver slot can be a linear louver slot.

[0010] According to this arrangement, an excessive reduction in lateral stiffness can be avoided by applying a linear slot as the first lamellar slot. Compared to a generally used corrugated lamellar slot, a linear lamellar slot reduces stiffness less. Therefore, applying a linear lamellar slot as the first lamellar slot can maintain adequate lateral stiffness of the shoulder block.

[0011] The pneumatic tire further incorporates a second lamellar slit, located in the tread area of ​​the shoulder block, extending in the tire's width direction and having one end connected to the main shoulder groove and another end reaching the smooth zone. The first lamellar slit is positioned at a point on an imaginary extension of the second lamellar slit.

[0012] According to this arrangement, the second lamellar slot, located in the tread area of ​​the shoulder block, increases the number of edges in contact with the ground. Consequently, traction and braking performance are improved. Furthermore, if the first lamellar slot is positioned along the imaginary extension of the second lamellar slot, the stiffness of the shoulder block can be balanced. More precisely, the ratio in which the side area is divided by the first lamellar slot in the shoulder block and the ratio in which the tread area is divided by the second lamellar slot in the shoulder block become essentially the same. In this case, any unbalanced stiffness is reduced, thereby minimizing uneven wear and improving durability.Furthermore, the first louver slot, located at the point on the imaginary extension of the second louver slot, is clearly recognizable as a louver slot with a shape that continues from the second louver slot. Accordingly, an excellent aesthetic appearance is achieved.

[0013] The pneumatic tire may further include a continuous lamellar slit located in a central area of ​​the shoulder block in the circumferential direction of the tire, extending through the tread area, the shoulder area, and the sidewall area. The smooth zone, the first lamellar slit, and the second lamellar slit may each be provided on either side of the continuous lamellar slit in the circumferential direction of the tire.

[0014] According to this arrangement, the continuous lamellar slot extends through the tread area, the shoulder area, and the sidewall. This allows the entire shoulder block to maintain adequate stiffness. Specifically, the continuous lamellar slot is located in the center of the shoulder block in the tire's circumferential direction. Consequently, the stiffness of the center area is kept low, while the stiffness of both sidewalls, which require high stiffness, is maintained at a high level. Furthermore, each of the two sidewalls contains the smooth zone, the first lamellar slot, and the second lamellar slot. This appropriately reduces the stiffness of the tread and sidewall areas, while maintaining the high stiffness of the shoulder area, which requires high stiffness. Effects of the invention

[0015] According to a pneumatic tire according to the present invention, a shoulder block comprises a smooth zone in both lateral regions of a shoulder area, except for a central region of the shoulder area in one circumferential direction of the tire. Accordingly, the stiffness of the shoulder block can be appropriately increased. Brief description of the drawing Fig. Figure 1 is a perspective view of an air tire according to an embodiment of the present invention; Fig. 2 is a flattened view of a tread area of ​​the in Fig. 1. The depicted pneumatic tire and the surrounding area of ​​the tread; Fig. 3 is a partially enlarged view of Fig. 2; Fig. Figure 4 is an enlarged view of a midrib; Fig. 5 is a section view along a line VV in Fig. 4; Fig. 6 is a section view along a line VI-VI in Fig. 4; Fig. Figure 7 is an enlarged view of a shoulder block; Fig. 8 is a sectional view along a line VIII-VIII of Fig. 7; Fig. 9 is a sectional view along a line IX-IX of Fig. 7; Fig. 10 is a sectional view along lines XX, X'-X' and X''-X'' in Fig. 7; and Fig. Figure 11 is a sectional view along lines XI-XI and XI'-XI' in Fig. 7. Description of embodiments

[0016] In the following description, the terms “upward to the right” and “downward to the right” are used in some cases to express a slope in a top view or tire radial view of a structure with a longitudinal direction, such as a groove and a lamellar slot, formed in a tread area.

[0017] The term "top right" refers to a condition where the longitudinal direction of the structure and one tire circumference direction are aligned by rotating the tire circumference clockwise at an acute angle around the intersection of the structure's longitudinal direction and the tire's circumference direction. The term "top right" also refers to a condition where the longitudinal direction of the structure and the tire circumference direction are aligned by rotating the tire width direction counterclockwise at an acute angle around the intersection of the structure's longitudinal direction and the tire's width direction.

[0018] The term "down-right" refers to a condition where the longitudinal direction of the structure and the circumferential direction of the tire are aligned by rotating the circumferential direction of the tire counterclockwise at an acute angle around the point of intersection of the longitudinal direction of the structure and the circumferential direction of the tire. The term "down-right" also refers to a condition where the longitudinal direction of the structure and the circumferential direction of the tire are aligned by rotating the circumferential direction of the tire clockwise at an acute angle around the point of intersection of the longitudinal direction of the structure and the circumferential direction of the tire.

[0019] In the following description, a plus sign is assumed to be given to an angle “to the upper right” formed by the structure having the longitudinal direction, such as a groove and a lamellar slot formed in the tread area, with the tire circumference direction or the tire width direction in a tire radial view, and a minus sign is given to an angle “to the lower right” formed in a similar way. (Overview of the running track area and its surroundings)

[0020] Fig. 1, Fig. 2 to Fig. Figure 3 each represents a tread area 2 of a pneumatic tire (hereinafter referred to as tire) 1 made of rubber according to an embodiment of the present invention and a surrounding area of ​​the tread area 2. The tire 1 is an M+S tire.

[0021] A tire circumference direction in the figures is designated by a reference symbol TC, and a tire width direction is designated by a reference symbol TW. A center line (equatorial line) of the tread area 2 in the tire width direction is designated by a reference symbol CL. Ground contact ends of one and the other end of the tread area 2 in the tire width direction are designated by the reference symbols GE1 and GE2, respectively. In the following description, the ground contact end GE1 or GE2 is sometimes simply referred to as a ground contact end GE when a distinction between the two ground contact ends GE1 and GE2 is not particularly necessary.

[0022] In this description, a zone of a tire's outer circumference located between two ground contact points GE1 and GE2 is referred to as the tread area 2. An area located outside the tread area 2 in the tire's width direction, intersecting a tire axial direction substantially at a right angle, and having a flat shape or relatively small curvature, is referred to as a side area 3. An area connecting the tread area 2 and the side area 3, and curved with a relatively strong curvature, is referred to as a shoulder area 4.

[0023] A central main groove 5, extending in the circumferential direction of the tire, is formed in a central zone of the tread area 2 in the width direction of the tire, more precisely, on the center line CL. The central main groove 5 does not have a linear shape, but rather a meandering or zigzag shape in the radial view of the tire.

[0024] With reference to Fig. 2 The zigzag shape of the central main groove 5 is formed by long groove sections 5a inclined upwards to the right and short groove sections 5b inclined downwards to the right, arranged alternately. Each of the long groove sections 5a is longer than each of the short groove sections 5b. The inclination angle α1 of each of the long groove sections 5a to the tire circumference is smaller than the inclination angle α2 of each of the short groove sections 5b to the tire circumference. The inclination angle α1 can be specified in a range of 1 degree to 20 degrees (inclusive), and the inclination angle α2 can be specified in a range of 5 degrees to 60 degrees (inclusive) such that it is greater than the inclination angle α1.

[0025] Shoulder grooves 6A and 6B, extending in the circumferential direction of the tire, are formed in the tread area 2 on the sides of the ground contact ends GE1 and GE2, respectively, with respect to the central groove 5. The two shoulder grooves 6A and 6B are each adjacent to the central groove 5 in the tire width direction. Each of the shoulder grooves 6A and 6B does not have a linear shape, but rather a meandering or zigzag shape in the tire radial view. In the following description, the shoulder groove 6A or 6B is sometimes simply referred to as a shoulder groove 6 when a distinction between the two shoulder grooves 6A and 6B is not particularly necessary.

[0026] With reference to Fig. 2 The zigzag shape of the main shoulder groove 6 is formed by long groove sections 6a inclined upwards to the right and short groove sections 6b inclined downwards to the right, arranged alternately. Each of the long groove sections 6a is longer than each of the short groove sections 6b. An inclination angle α3 of each of the long groove sections 6a to the tire circumference direction is smaller than an inclination angle α4 of each of the short groove sections 6b to the tire circumference direction. The inclination angle α3 can be set in a range of 1 degree to 30 degrees (inclusive), and the inclination angle α4 can be set in a range of 5 degrees to 60 degrees (inclusive) such that it is greater than the inclination angle α3. The long groove section 6a of the main shoulder groove 6 is shorter than the long groove section 5a of the main center groove 5 and, according to the present embodiment, is set to approximately half the length of the long groove section 5a.

[0027] A central rib 7A, extending in the circumferential direction of the tire and formed in the central zone of the tread area 2 in the tire width direction, is bounded by the central main groove 5 and the shoulder main groove 6A. A central rib 7B, extending in the circumferential direction of the tire and formed in the central zone in the tire width direction, is bounded by the central main groove 5 and the shoulder main groove 6B. In the following description, the central rib 7A or 7B is sometimes simply referred to as a central rib 7 when a distinction between the two central ribs 7A and 7B is not particularly necessary.

[0028] A plurality of shoulder lateral grooves 8A and 8B spaced apart in the tire circumferential direction are provided in two shoulder zones of the tread area 2 on one side and the other side in the tire width direction, i.e., two zones adjacent to the ground contact points GE1 and GE2.

[0029] Each of the shoulder lateral grooves 8A extends essentially in the tire width direction, and one end of each is connected to a kink point of the zigzag shape of the main shoulder groove 6A, while the other end extends beyond the ground contact end GE1 and the shoulder area 4. The other end of each of the shoulder lateral grooves 8A is located in the side area 3. The kink point of the zigzag shape of the main shoulder groove 6 refers here to a point where the direction of extension of the main shoulder groove 6 changes in the tire width direction. In other words, the kink point refers to a point where a right-upward slope and a right-downward slope alternate.

[0030] Similarly, each of the shoulder lateral grooves 8B extends substantially in the tire width direction, with one end of each end connected to the shoulder main groove 6B, and the other end located in the side area 3 outside the ground contact end GE2 and the shoulder area 4 in the tire width direction.

[0031] In the following description, the shoulder lateral grooves 8A or 8B are in some cases simply referred to as shoulder lateral grooves 8 when a distinction between the two shoulder lateral grooves 8A and 8B is not particularly needed.

[0032] A plurality of shoulder blocks 9A, each bounded by the main shoulder groove 6A and the two shoulder lateral grooves 8A adjacent to each other in the circumferential direction of the tire, is arranged in the circumferential direction of the tire on a region of the tread area 2 on the side of the ground contact end GE1.

[0033] Each of the shoulder blocks 9A has an elongated shape in the tire width direction. Each inner end of the shoulder blocks 9A in the tire width direction lies in the tread area 2. Each of the shoulder blocks 9A extends beyond the ground contact end GE1 and the shoulder area 4 outwards in the tire width direction. Each outer end of the shoulder blocks 9A in the tire width direction lies in the sidewall area 3.

[0034] Similarly, a plurality of shoulder blocks 9B, each bounded by the main shoulder groove 6B and the two adjacent shoulder lateral grooves 8B in the tire circumference direction, are arranged in the tire circumference direction in a region of the tread area 2 on the side of the ground contact end GE2. Each of the shoulder blocks 9B has an elongated shape in the tire width direction. Each inner end of the shoulder blocks 9B in the tire width direction lies in the tread area 2, while each outer end of the shoulder blocks 9B in the tire width direction lies in the side area 3.

[0035] In the following description, shoulder blocks 9A or 9B are in some cases simply referred to as shoulder blocks 8 when a distinction between shoulder blocks 9A and 9B is not particularly needed.

[0036] A plurality of central grooves 11 are provided in the central rib 7 at fixed intervals in the tire's circumferential direction. The central groove 11 is positioned in the same circumferential direction as the shoulder lateral groove 8. The identical position here refers to a position such that at least a portion of the central groove 11 and the shoulder lateral groove 8 overlap each other in the tire's circumferential direction. Each of the central grooves 11 is inclined upwards and to the right. One end (proximal end) of each of the central grooves 11 is connected to the central main groove 5, and the other end (distal end) terminates in the central rib 7. Each distal end of the central grooves 11 has a curved shape. As detailed below, each of the pair of sidewalls 11d that bound each of the central grooves 11 has a shoulder 11h and forms two edges, i.e., a major edge 11i and a minor edge 11j (see also Fig. 5) Paragraph 11h only needs to be provided on one of the pair of side walls 11d.

[0037] A plurality of side grooves 12 are provided in the central rib 7 at fixed intervals in the tire's circumferential direction. Each of the side grooves 12 is inclined upwards and to the right. One end (proximal end) of each of the side grooves 12 is connected to the shoulder main groove 6, and the other end (distal end) terminates in the central rib 7. As detailed below, each of the side walls 12b, which bound each of the side grooves 12, has a shoulder 12f and forms two edges, i.e., a main edge 12g and a secondary edge 12h (see also Fig. 6). Paragraph 12f only needs to be provided on one of the pair of side walls 12b.

[0038] Two linear lamellar slots 13A and 13B are provided separately in the circumferential direction of the tire in the center rib 7 at each of the areas opposite the center grooves 11 in the tire width direction. One end (proximal end) of each of the linear lamellar slots 13A and 13B is connected to the shoulder main groove 6, and the other end (distal end) terminates in the center rib 7. Both linear lamellar slots 13A and 13B are inclined downwards and to the right. The respective linear lamellar slots 13A and 13B extend substantially parallel to each other. The center rib 7 contains linear lamellar slots 13C inclined downwards and to the right, with a gap left between them and the linear lamellar slot 13B in the circumferential direction of the tire. One end (proximal end) of each of the linear lamellar slits 13C is connected to the shoulder groove 6, and the other end (distal end) terminates in the midrib 7.

[0039] Two linear lamellar slots 14A and 14B are provided separately in the circumferential direction of the tire in the central rib 7 at each of the areas opposite the side grooves 12 in the tire width direction. One end (proximal end) of each of the linear lamellar slots 14A and 14B is connected to the central main groove 5, and the other end (distal end) terminates in the central rib 7. Both linear lamellar slots 14A and 14B are inclined downwards and to the right. Furthermore, the linear lamellar slots 14A and 14B extend substantially parallel to each other. The central rib 7 contains linear lamellar slots 14C inclined downwards and to the right, with a gap left between them and the linear lamellar slot 14B in the circumferential direction of the tire. One end (proximal end) of each of the linear lamellar slits 14C is connected to the shoulder groove 6, and the other end (distal end) terminates in the midrib 7.

[0040] The central rib 7 contains three types of corrugated lamellar slots 15A to 15C in an area between each of the central grooves 11 and the side groove 12 adjacent to the corresponding central groove 11 in the tire's circumferential direction. Each of the corrugated lamellar slots 15A to 15C is inclined upwards and to the right. One end of the corrugated lamellar slot 15A adjacent to the center groove 11 in the circumferential direction of the tire is connected to the central main groove 5, and the other end terminates in the central rib 7. One end of the corrugated lamellar slot 15C adjacent to the side groove 12 in the circumferential direction of the tire is connected to the shoulder main groove 6, and the other end terminates in the central rib 7. One end of the corrugated lamellar slot 15B located between the corrugated lamellar slots 15A and 15C is connected to the central main groove 5, and the other end is connected to the shoulder main groove 6.

[0041] As detailed below, each of the pair of sidewalls 8d, which delimit each of the shoulder lateral grooves 8, has a shoulder 8h. A corner of the shoulder block 9 extends in the tire width direction and has two edges, i.e., a major edge 9a and a minor edge 9b (see Fig. 8 and Fig. 9). Paragraph 8h only needs to be provided on one of the pair of side walls 8d.

[0042] A single non-continuous lamellar slot (continuous lamellar slot) 21 is provided in a central region of the shoulder block 9 in the circumferential direction of the tire and extends in the tire width direction through the tread region 2, the shoulder region 4, and the sidewall region 3. One end of the non-continuous lamellar slot 21 is connected to the main shoulder groove 6, and the other end extends beyond the ground contact end G outwards in the tire width direction. The other end of the non-continuous lamellar slot 21 terminates at a boundary between the shoulder region 4 and the sidewall region 3 (see figure). Fig. 2) As detailed below, the non-continuous lamellar slot 21 has alternating deep areas 21a, 21c and 21e and shallow areas 21b and 21d extending in different directions from the tire width direction, and generally has a zigzag shape in the tire radial view.

[0043] A pair of compound lamellar slots (second lamellar slots) 22, provided in the tread area 2 of the shoulder block 9, is located on either side of each of the non-continuous lamellar slots 21 in the circumferential direction of the tire. One end of the compound lamellar slots 22 is connected to the main shoulder groove 6, and the other end terminates in the shoulder block 9. Each of the compound lamellar slots 22 contains a linear lamellar slot area 22a on one end and a corrugated lamellar slot area 22b on the other end. A distal end of the other end of the compound lamellar slot 22 forms a smooth zone 4a of the side area 3 and contains no protrusions or depressions, such as lamellar slots and projections. In other words, the compound lamellar slot 22 extends from the main shoulder groove 6 to the smooth zone 4a.The smooth zone 4a is located in both lateral regions of the shoulder region 4, except for a central region of the shoulder region 4 in the tire circumference direction (the region where the non-continuous lamellar slot 21 is provided). Both lateral regions of the shoulder block 9 in the tire circumference direction refer here to regions that each have a length of 40% of the length of the shoulder block 9 in the tire circumference direction and extend from the side of the shoulder block 9 in the tire circumference direction.

[0044] A pair of linear lamellar slots (first lamellar slots) 23, extending substantially in the tire width direction or the tire radial direction, is provided in the sidewall region 3 and the shoulder region 4 in an outer zone of the shoulder block 9 in the tire width direction. Each of the linear lamellar slots 23 is located at a position on an imaginary extension from the compound lamellar slot 22 and has one end located at the shoulder region 4 and the other end located at the sidewall region 3. More precisely, one end of the linear lamellar slot 23 reaches the smooth zone 4a of the shoulder region 4. Furthermore, the pair of linear lamellar slots 23 is arranged such that the non-continuous lamellar slot 21 lies between them in the tire circumferential direction.

[0045] Continuous protrusion areas 24 are provided in side area 3. (Details of the midrib)

[0046] The midrib 7 is described below mainly with reference to Fig. 4 described in detail. As described above, the central rib 7 contains the central notches 11, the side notches 12, the linear lamellar slots 13A to 13C, the linear lamellar slots 14A to 14C and the corrugated lamellar slots 15A to 15C.

[0047] Each of the center rib units 7C, which are formed by dividing the center rib 7 for each kink point of the center main groove 5 in the tire circumferential direction (see the frame shown in Fig. 2 (indicated by dashed lines) is provided in accordance with the two shoulder blocks 9.

[0048] Each of the central grooves 11 contains a trunk section 11a, the proximal end of which is connected to the central main groove 5, and a distal end section 11b, which is bent with respect to a distal end of the trunk section 11a. More precisely, the trunk section 11a of the central groove 11 is associated with the inflection point of the zigzag shape of the central main groove 5. The inflection point of the zigzag shape of the central main groove 5 refers here to a point at which the direction of extension of the central main groove 5 changes in the tire width direction. In other words, the inflection point refers to a point where a right-upward inclination and a right-downward inclination alternate. The width of the central groove 11 gradually decreases from a proximal end of the trunk section 11a to a distal end of the distal end section 11b. According to the present embodiment, the angle θ1 of the body area 11a with respect to the tire circumferential direction is 73 degrees.The angle θ2 of the distal end region 11b with respect to the tire circumference direction is 30 degrees, which is smaller than the angle θ1. The angle θ1 can be set in a range of 30 degrees to 85 degrees (inclusive), while the angle θ2 can be set within a range of 0 degrees to 60 degrees (inclusive), smaller than the angle θ1.

[0049] Also with reference to Fig. In the present embodiment, each of the central grooves 11 is bounded by a bottom wall 11c and a pair of opposing side walls 11d. Each of the side walls 11d comprises a first region 11e, a second region 11f, and a third region 11g. According to the present embodiment, the first region 11e, the second region 11f, and the third region 11g of each of the side walls 11d are all flat surfaces. The first region 11e extends substantially in a tire radial direction from the bottom wall 11c to a surface of the central rib 7, perpendicular to a direction of extension of the central groove 11 in a sectional view. In the same sectional view, the second region 11f extends substantially in the tire circumferential direction, with one end of the second region 11f being connected to an upper end of the first region 11e to increase the width of the central groove 11.In the same sectional view, the third region 11g has a lower end connected to the other end of the second region 11f and an upper end connected to the surface of the central rib 7.

[0050] In the sectional view, perpendicular to the direction of extension of the central groove 11, the direction of extension of each of the sidewalls 11d changes sharply at a junction between the first region 11e and the second region 11f. More precisely, a step 11h is formed at the junction between the first region 11e and the second region 11f. This junction is adjacent to the tread region 2 and, according to the present embodiment, is set back from the surface of the tread region 2 by a step. The step 11h thus formed creates two edges at an opening edge of the central groove 11, i.e., the main edge 11i on the surface side of the central rib 7 and the secondary edge 11j within the main edge 11i in the tire radial direction. The main edge 11i is formed at a junction between the surface of the central rib 7 and the third region 11g of the sidewall 11d.The secondary edge 11j is formed at a connection area between the first area 11e of the side wall 11d and the second area 11f of the side wall 11d.

[0051] The width W1 of the paragraph 11h (width of the second area 11f of the side wall 11d) can be specified within a range from 0.1 to 1.0 times (inclusive) the width W2 of the center notch 11 at the first area 11e. The width W1 can be specified within a range of 0.3 mm to 3 mm (inclusive). The width W2 of the center notch 11 can be specified within a range of 1.2 mm to 10 mm (inclusive). Accordingly, the width of the center notch 11, including the width W1 of the paragraph 11h, can be specified within a range of 1.8 mm to 16 mm (inclusive). A depth position DE1 of the shoulder 11h from the surface of the central rib 7 (height of the third region 11g of the side wall 11d) can be set within a range from 0.05 times to 0.5 times (inclusive) a depth DE2 of the central notch 11. The depth DE2 of the central notch 11 can be set within a range of 2 mm to 13 mm (inclusive).According to the present embodiment, an angle y1 formed by the second region 11f of the side wall 11d to the surface of the central rib 7 in the sectional view, perpendicular to the direction of extension of the central notch 11, is 0°. The angle y1 can be set within a range of -30 degrees to 30 degrees (inclusive). (The angle γ1 has a positive value in the clockwise direction in Fig. 5.)

[0052] The width of the side groove 12 gradually decreases from the proximal end to the distal end. According to the present embodiment, the angle θ3 of the side groove 12 to the tire circumference is 70 degrees. The angle θ3 can be set in a range of 30 degrees to 85 degrees (inclusive).

[0053] With reference to Fig. In the present embodiment, the side groove 12 is bounded by a bottom wall 12a and a pair of opposing side walls 12b. Each of the side walls 12b comprises a first region 12c, a second region 12d, and a third region 12e. According to the present embodiment, the first region 12c, the second region 12d, and the third region 12e of the side wall 12b are all flat surfaces. The first region 12c extends substantially in the tire radial direction from the bottom wall 12a to the surface of the central rib 7, perpendicular to one direction of extension of the side groove 12 in a sectional view. In the same sectional view, the second region 12d extends substantially in the tire circumferential direction, with one end connected to an upper end of the first region 12c to increase the width of the side groove 12.In the same sectional view, the third region 12e has a lower end connected to the other end of the second region 12d and an upper end connected to the surface of the central rib 7.

[0054] In the sectional view, perpendicular to the direction of extension of the side groove 12, the direction of extension of the sidewall 12b changes sharply at a junction between the first region 12c and the second region 12d. More precisely, the shoulder 12f is formed at the junction between the first region 12c and the second region 12d. The shoulder 12f thus formed creates two edges on an opening edge of the side groove 12, i.e., the main edge 12g on the surface side of the center rib 7 and the secondary edge 12h, located within the main edge 12g in the tire radial direction. The main edge 12g is formed at a junction between the surface of the center rib 7 and the third region 12e of the sidewall 12b. The secondary edge 12h is formed at a junction between the first region 12c and the second region 12d of the sidewall 12b.

[0055] The width W3 of paragraph 12f (width of the second area 12d of the side wall 12b) can be specified within a range from 0.1 to 1.0 times (inclusive) the width W4 of the side notch 12 at the first area 12c. The width W4 can be specified within a range of 0.3 mm to 3 mm (inclusive). The width W4 of the side notch 12 can be specified within a range of 1.2 mm to 10 mm (inclusive). Accordingly, the width of the side notch 12, including the width W3 of paragraph 12f, can be specified within a range of 1.8 mm to 16 mm (inclusive). The depth position DE3 of the shoulder 12f from the surface of the side notch 12 (height of the third region 12e of the side wall 12b) can be specified within a range from 0.05 times to 0.5 times (inclusive) a depth DE4 of the side notch 12. The depth DE4 of the side notch 12 can be specified within a range from 2 mm to 13 mm (inclusive).According to the present embodiment, an angle y2 formed by the second region 12d of the side wall 12b to the surface of the side notch 12 in the sectional view, perpendicular to the direction of extension of the side notch 12, is 0°. The angle y2 can be set within a range of -30 degrees to 30 degrees (inclusive). (The angle y2 has a positive value in the clockwise direction.) Fig. 6 on.)

[0056] As described above, the center rib 7 contains two linear lamellar slots 13A and 13B in the area opposite the center groove 11 in the tire width direction. The condition of "opposite in the tire width direction" refers here to a condition in which at least a portion of the linear lamellar slots 13A and 13B overlaps the center groove 11 in the tire circumference direction. While the center groove 11 is inclined upwards to the right (angle θ1 is in the range of 30 degrees to 85 degrees (inclusive), and angle θ2 is in the range of 0 degrees to 60 degrees (inclusive)), the linear lamellar slots 13A and 13B are inclined downwards to the right. An angle θ4 of the linear lamellar slots 13A and 13B to the tire radial direction can be set within a range of -30 degrees to -85 degrees (inclusive).In this case, the linear sipes 13A and 13B extend such that they form the angle θ4 with a different sign than the angles θ1 and θ2 of the center groove 11 with respect to the tire's circumferential direction. Accordingly, an imaginary line indicating the direction of extension of the center groove 11 and imaginary lines indicating the directions of extension of the linear sipes 13A and 13B form a polygonal line extending in one direction (in ). Fig. 4 upwards) in the direction of the tire's circumference.

[0057] The distal end of the central groove 11 and the distal end closest to the central main groove 5 under the distal ends of the linear lamellar slots 13A and 13B, which are opposite the central groove 11 in the tire width direction, can lie in the middle zone of the central rib 7 in the tire width direction. More precisely, these distal ends can lie within a region of width CRW1 whose center lies in the center of the central rib 7 in the width direction (indicated by the reference symbol CRC in Fig. 4) The width CRW1 can be set here within a range from 0.1 times to 0.4 times (inclusive) a width CRW0 (average width) of the central rib 7.

[0058] The width of each linear louver slot 13A and 13B can be specified within a range of 0.3 mm to 1.5 mm (inclusive). The depth of each linear louver slot 13A and 13B can be specified within a range of 2 mm to 13 mm (inclusive).

[0059] As described above, the two linear sipes 14A and 14B are located in the center rib 7 in the area opposite the side groove 12 in the tire width direction. The term "opposite in the tire width direction" refers to a condition where at least part of the linear sipes 14A and 14B overlap the center groove 12 in the tire circumference direction. While the side groove 12 is inclined upwards to the right (the angle θ3 is in the range of 30° to 85° (inclusive)), the linear sipes 14A and 14B are inclined downwards to the right. An angle θ5 of the linear sipes 14A and 14B to the tire radial direction can be specified within a range of -30 degrees to -85 degrees (inclusive). In this case, the linear lamellar slots 14A and 14B extend such that they form the angle θ5 with a different sign than the sign of the angle θ3 of the side groove 12 to the tire circumferential direction.Accordingly, an imaginary line indicating a direction of extension of the side notch 12, and imaginary lines indicating directions of extension of the linear lamellar slots 14A and 14B, form a polygonal line extending in one direction (in . Fig. 4 downwards) in the direction of the tire's circumference.

[0060] The distal end of the side groove 12 and the distal end closest to the shoulder main groove 6 under the distal ends of the linear lamellar slots 14A and 14B, which are opposite the side groove 12 in the tire width direction, may lie in a region of the width CRW1 described above.

[0061] The width of each linear louver slot 14A and 14B can be specified within a range of 0.3 mm to 1.5 mm (inclusive). The depth of each linear louver slot 14A and 14B can be specified within a range of 2 mm to 13 mm (inclusive). (Details of the lateral scapular groove and the shoulder block)

[0062] The shoulder lateral grooves 8 and the shoulder blocks 9 are described below mainly with reference to Fig. 7 described in detail. As described above, each of the shoulder blocks 9 contains the one non-continuous lamellar slot 21, the two compound lamellar slots 22 and the two linear lamellar slots 23.

[0063] Each of the shoulder lateral grooves 8 contains an inner region 8a, connected to the main shoulder groove 6, and an outer region 8b, which extends outwards beyond the ground contact end GE in the tire width direction, one end being connected to the inner region 8a. Also with reference to Fig. 2 is the other end of the outer area 8b at the border between the shoulder area 4 and the side area 3, as described above.

[0064] The shoulder lateral groove 8 extends essentially in the tire width direction. However, the inner region 8a and the outer region 8b have different inclinations in the tire width direction. The inner region 8a is inclined upwards and to the right. An angle θ6 of the inner region 8a to the tire width direction can be specified within a range of 2 degrees to 45 degrees (inclusive). The outer region 8b is inclined downwards and to the right. An angle θ7 of the outer region 8b to the tire width direction can be specified within a range of -2 degrees to -20 degrees (inclusive).

[0065] The size of the inner area 8a of the shoulder lateral groove 8 in the tire width direction is smaller than the size of the outer area 8b of the shoulder lateral groove 8 in the tire width direction. The length of the inner area 8a can be specified within a range of 0.1 to 0.4 times (inclusive) the length of the outer area 8b.

[0066] Also with reference to Fig. 8 and Fig. In this embodiment, the width W5 of the inner region 8a of the shoulder lateral groove 8 is specified as smaller than the width W6 of the outer region 8b of the shoulder lateral groove 8. The width W5 of the inner region 8a of the shoulder lateral groove 8 gradually decreases towards the main shoulder groove 6. According to this embodiment, the depth DE5 of the inner region 8a of the shoulder lateral groove 8 is matched to the depth DE6 of the outer region 8b of the shoulder lateral groove 8. The depth DE5 of the inner region 8a may be specified as smaller than the depth DE6 of the outer region 8b. Each of the depths DE5 and DE6 of the shoulder lateral groove 8 may be specified within a range of 2 mm to 13 mm (inclusive).

[0067] Furthermore, also with reference to Fig. 8 and Fig. In the present embodiment, the shoulder lateral groove 8 is bounded by a bottom wall 8c and a pair of opposing side walls 8d. Each of the side walls 8d comprises a first region 8e, a second region 8f, and a third region 8g. According to the present embodiment, the first region 8e, the second region 8f, and the third region 8g of the side wall 8d are all flat surfaces. The first region 8e extends substantially in the tire radial direction from the bottom wall 8c to the surface of the shoulder block 9, perpendicular to one direction of extension of the shoulder lateral groove 8 in a sectional view. In the same sectional view, the second region 8f extends substantially in the tire circumferential direction, with one end of the second region 8f being connected to an upper end of the first region 8e to increase the width of the shoulder lateral groove 8.In the same sectional view, the third area 8g has a lower end connected to the other end of the second area 8f and an upper end connected to the surface of the shoulder block 9.

[0068] In the sectional view, perpendicular to the direction of extension of the shoulder lateral groove 8, the direction of extension of the sidewall 8d changes sharply at a junction between the first region 8e and the second region 8f. More precisely, the step 8h is formed at the junction between the first region 8e and the second region 8f. As described above, the shoulder lateral groove 8 and the main shoulder groove 6 define the shoulder block 9. More precisely, the sidewall 8d of the shoulder lateral groove 8 and the surface of the tread area 2 create a corner of the shoulder block 9 that extends in the tire width direction. Due to the step 8h thus provided on the sidewall 8d of the shoulder lateral groove 8, a corner of the shoulder block 9 that extends in the tire width direction has not a single edge, but two edges.More precisely, the corner of the shoulder block 9, extending in the tire width direction, has a major edge 9a on the side of the front surface of the shoulder block 9 and a minor edge 9b within the major edge 9a in the tire radial direction. The major edge 9a is formed at a junction between the surface of the shoulder block 9 and the third region 8g of the sidewall 8d of the shoulder lateral groove 8. The minor edge 9b is formed at a junction between the first region 8e of the sidewall 8d and the sidewall 8d of the shoulder lateral groove 8.

[0069] A width W7 of the shoulder 8h (width of the second region 8f of the side wall 8d) can be defined within a range from 0.1 to 1.0 times (inclusive) each of the widths W5 and W6 of the shoulder lateral groove 8 at the first region 8e. A depth position DE7 of the shoulder 8h from the surface of the shoulder block 9 (height of the third region 8g of the side wall 8d) can be defined within a range from 0.05 to 0.5 times (inclusive) each of the depths DE5 and DE6 of the shoulder lateral groove 8. According to the present embodiment, an angle y3 formed by the second region 8f of the side wall 8d to the surface of the shoulder block 9 in the sectional view, perpendicular to the extension direction of the shoulder lateral groove 8, is 0°. The angle y3 can be defined within a range of -30 degrees to 30 degrees (inclusive). (The angle y3 has a positive value in the clockwise direction in Fig. 8 and Fig. 9 on.)

[0070] Each of the non-continuous lamellar slots 21 extends essentially in a zigzag shape in the tire width direction from the main shoulder groove 6 to the boundary between the shoulder area 4 and the side area 3 (see also Fig. 2) in the tire radial view. Each of the non-continuous sipes 21 contains two types of alternatingly arranged elements, i.e., deep areas 21a, 21c, and 21e, and shallow areas 21b and 21d. These elements are arranged in the following order, from the main shoulder groove 6 outwards in the tire width direction: deep area 21a, shallow area 21b, deep area 21c, shallow area 21d, and deep area 21e. More precisely, one end of the deep area 21a is connected to the main shoulder groove 6, and the other end is connected to one end of the shallow area 21b. The other end of the shallow area 21b is connected to one end of the deep area 21c. The other end of the deep area 21c is connected to one end of the shallow area 21d. The other end of the shallow area 21d is connected to one end of the deep area 21e. The other end of the deep area 21e ends in shoulder block 9.

[0071] Also with reference to Fig. 10 and Fig. 11 The non-continuous lamellar slot 21 contains a single shallow groove 21A, extending from the deep area 21a, which is the element connected to the main shoulder groove 6, to the deep area 21e, which is the element furthest from the main shoulder groove 6. In other words, the shallow groove 21A is provided for all the elements that form the non-continuous lamellar slot 21, i.e., the deep areas 21a, 21c, and 21e, and the shallow areas 21b and 21d. The shallow groove 21A opens to the surface of the shoulder block 9.

[0072] Lamellar slot body regions 21f, 21g and 21h, which communicate with the shallow groove 21A, are further provided in the deep regions 21a, 21c and 21e. Upper ends of the lamellar slot body regions 21f, 21g and 21h communicate with a lower part of the shallow groove 21A. According to the present embodiment, each of the lamellar slot body regions 21f, 21g and 21h is a linear lamellar slot.

[0073] Each of the shallow areas 21b and 21d lacks a lamellar slot body area but consists only of the shallow groove 21A. Accordingly, the lamellar slot body areas 21f, 21g, and 21h of the deep areas 21a, 21c, and 21e are not connected to each other. In other words, the deep area 21a and the deep area 21c are spatially connected only by the shallow groove 21A, which forms the shallow area 21b located between the deep area 21a and the deep area 21c. Similarly, the deep area 21c and the deep area 21e are spatially connected only by the shallow groove 21A, which forms the shallow area 21d located between the deep area 21c and the deep area 21e.

[0074] With reference to Fig. In the present embodiment, 7 are all elements forming the non-continuous lamellar slot 21, i.e., the deep areas 21a, 21c, and 21e and the shallow areas 21b and 21d, linear in the tire radial view. The size, i.e., the length in the tire width direction, is determined such that a length L1 of the deep area 21a is substantially equal to a length L2 of the deep area 21c, and that a length L3 of the deep area 21e is sufficiently greater than either length L1 or L2 of the deep areas 21a and 21c. Each of the lengths L1, L2, and L3 of the deep areas 21a, 21c, and 21e can be specified within a range of 0.1 to 0.5 times (inclusive) a total length L4 of the shoulder block 9 in the tire width direction. Each of the lengths L5 and L6 of the shallow areas 21b and 21d is sufficiently smaller than each of the lengths L1, L2 and L3 of the deep areas 21a, 21c and 21e.Each of the lengths L5 and L6 of the shallow areas 21b and 21d can be set within a range of 0.1 times to 0.5 times the smallest length among the lengths L1, L2 and L3 of the deep areas 21a, 21c and 21e.

[0075] The deep area 21c is offset relative to the deep area 21a in the tire circumferential direction. The deep area 21e is offset relative to the deep area 21c in the tire circumferential direction. According to the present embodiment, the deep area 21c is directed downwards in Fig. 7 offset against the deep area 21a, while the deep area 21e is offset downwards into Fig. 7 is offset against the deep area 21c. According to the present embodiment, each of the angles θ8, θ9 and θ10 formed by the deep areas 21a, 21c and 21e with respect to the tire width direction is 0°. Each of the angles θ8 to θ10 can be set in a range from -20 degrees to 20 degrees (inclusive).

[0076] According to the present embodiment, the flat areas 21b and 21d are inclined downwards and to the right. Each of the angles θ11 and θ12 formed by the flat areas 21b and 21d with respect to the tire width direction is -30 degrees. In a case where the deep areas 21a, 21c, and 21e are offset as in the present embodiment, each of the angles θ11 and θ12 can be set within a range of -2 degrees to -45 degrees (inclusive). In a case where, unlike in the present embodiment, the deep area 21c is inclined upwards, Fig. 7 is offset against the deep area 21a, and in which the deep area 21e is moved upwards into Fig. Since 7 is offset against the deep region 21c, each of the shallow regions 21b and 21d has a slope to the upper right. In this case, each of the angles θ11 to θ12 can be set within a range of 2 degrees to 45 degrees (inclusive). Accordingly, each of the absolute values ​​of the angles θ11 to θ12 can be set within a range of 2 degrees to 45 degrees (inclusive).

[0077] Also with reference to Fig. 10 and Fig. 11 The flat groove 21A is bounded by a pair of sidewalls 21i opposing each other in the tire circumferential direction. Each of the sipe-slot body regions 21f, 21g and 21h is bounded by a bottom wall 21j, which opposes an opening of the flat groove 21A in the tire radial direction, and a pair of sidewalls 21k.

[0078] Each of the side walls 21i that bound the flat groove 21A has a chamfered shape in a sectional view, perpendicular to one direction of extension of the flat groove 21A. More precisely, in this sectional view, the side wall 21i is inclined towards the surface of the shoulder block 9. According to the present embodiment, the angle of inclination y4 of the right side wall 21i to the surface of the shoulder block 9 is Fig. 10 and Fig. 11 45 degrees. The inclination angle y4 can be set in a range from 5 degrees to 60 degrees (inclusive). In the present embodiment, the inclination angle of the left side wall 21i to the surface of the shoulder block 9 is Fig.10 and 11 -45 degrees and can be set in a range of -5 degrees to -60 degrees (inclusive). In other words, an absolute value of the inclination angle y4 of the side wall 21i to the shoulder block 9 can be set in a range of 5 degrees to 60 degrees (inclusive).

[0079] The depth DE8 of the shallow groove 21f can be specified within a range from 0.05 to 0.5 times (inclusive) a total depth DE9 of the deep areas 21a, 21c, and 21e (the sum of the depth DE8 of the shallow groove 21A and the depth DE9 of the lamellar slot body areas 21f, 21g, and 21h). A maximum width of the shallow groove 21A, i.e., a maximum width W8 of an opening of the shallow groove 21A (corresponding to openings of the deep areas 21a, 21c, and 21e and the shallow areas 21b and 21d) in the sectional view perpendicular to the extension direction of the shallow groove 21A, can be specified within a range from 1.2 to 5 times (inclusive) a width W9 of the lamellar slot body areas 21f, 21g, and 21h.

[0080] The linear sipe area 22a of the compound sipe 22 is located in a region corresponding to the inner region 8a (with a relatively small groove width W5) of the shoulder lateral groove 8 in the tire's circumferential direction. Accordingly, a portion of the linear sipe area 22a overlaps the inner region 8a in the tire's width direction. The corrugated sipe area 22b of the compound sipe 22 is located in a region corresponding to the outer region 8b (with a relatively large groove width W6) of the shoulder lateral groove 8 in the tire's circumferential direction. Accordingly, the corrugated sipe area 22b overlaps the outer region 8b in the tire's width direction.

[0081] The depth of the areas of the compound lamellar slot 22 (designated by reference numbers 22c, 22e and 22g), which correspond to the deep areas 21a, 21c and 21e of the non-continuous lamellar slot 21 in the tire circumferential direction, is specified as smaller than the depth of areas of the compound lamellar slot 22 (designated by reference numbers 22d and 22f), which correspond to the shallow areas 21b and 21d of the non-continuous lamellar slot 21 in the tire circumferential direction.

[0082] The operational effects achieved by the tire 1 according to the present embodiment are described below.

[0083] According to the present embodiment, the shoulder region 4 of the shoulder block 9 includes the smooth zone 4a. In this case, the stiffness of the shoulder region 4 can be higher than that of a shoulder region 4 containing a lamellar slot. In particular, the smooth zone 4a is provided in both lateral regions of the shoulder region 4, except for the central region of the shoulder region, in the circumferential direction of the tire. Accordingly, the stiffness of both end regions of the shoulder block 9 can be increased in the circumferential direction of the tire. From the perspective of steering stability, durability, and other aspects, it is preferable for one end region of the shoulder block 9 to have a higher stiffness than that of the central region of the shoulder block 9. Accordingly, an arrangement that increases the stiffness of both end regions of the shoulder block 9, such as the arrangement described above, is an effective arrangement.Furthermore, lateral region 3 is located outside a ground contact area. In this case, lateral region 3 does not need to exhibit a high stiffness equivalent to that of shoulder region 4. An excessive increase in the stiffness of lateral region 3 is therefore avoided by the presence of the linear lamellar slot 23 provided in lateral region 3. Accordingly, an appropriate increase in the stiffness of shoulder region 4 is achievable without an excessive increase in the stiffness of lateral region 3 of shoulder block 9.

[0084] According to the present embodiment, an excessive reduction in the stiffness of the side region 3 can be avoided by using the lamellar slot 23. Compared to a generally used corrugated lamellar slot, a linear lamellar slot reduces stiffness less than the corrugated lamellar slot. Accordingly, the linear lamellar slot 23 provided in the side region 3 can maintain an adequate stiffness of the side region 3 of the shoulder block 9.

[0085] According to the present embodiment, the compound lamellar slot 22 provided in the tread area 2 of the shoulder block 9 increases the number of edges in contact with the ground. This can improve traction and braking performance. Furthermore, when the linear lamellar slot 23 is located on the imaginary extension of the compound lamellar slot 22, the stiffness of the shoulder block 9 is balanced. More precisely, the ratio in which the side area 3 is divided by the linear lamellar slot 23 in the shoulder block 9 and the ratio in which the tread area 2 is divided by the compound lamellar slot 22 in the shoulder block 9 are essentially equalized. In this case, any unbalanced stiffness is reduced, thereby reducing uneven wear and improving durability.Furthermore, the linear louver slot 23, which is provided at the point on the imaginary extension of the compound louver slot 22, is clearly recognizable as a louver slot having a shape that continues from the compound louver slot 22. Accordingly, an excellent aesthetic appearance is achievable. The louver slot to be provided at the point of the imaginary extension of the compound louver slot 22 need not be linear, but can, for example, be a corrugated louver slot.

[0086] According to the present embodiment, the non-continuous lamellar slot 21 extends through the tread area 2, the shoulder area 4, and the sidewall area 3. In this case, the entire shoulder block 9 maintains adequate stiffness. In particular, the non-continuous lamellar slot 21 is provided in the central area of ​​the shoulder block 9 in the circumferential direction of the tire. Accordingly, the stiffness of the central area is low, while the stiffness of both sidewall areas, which require high stiffness, is maintained at a high level. Furthermore, each of the sidewall areas includes the smooth zone 4a, the linear lamellar slot 23, and the compound lamellar slot 22. Accordingly, the stiffness of the tread area 2 and the sidewall area 3 is appropriately reduced, while the stiffness of the shoulder area 4, which requires high stiffness, is maintained at a high level.

[0087] The present invention is not limited to the particular embodiment described herein. Various modifications can be made without departing from the scope of the present invention. List of reference symbols

[0088] 1: Tire, 2: Tread area, 3: Side area, 4: Shoulder area, 5: Central groove, 6; 6A; 6B: Shoulder groove, 7; 7A; 7B: Central rib, 8; 8A; 8B: Shoulder lateral groove, 8a: Inner area, 8b: Outer area, 8c: Bottom wall, 8d: Side wall, 8e: First area, 8f: Second area, 8g: Third area, 8h: Heel, 9; 9A; 9B: Shoulder block, 9a: Main edge, 9b: Secondary edge, 9c; 9d: Zone, 11: Central notch, 11a: Trunk area, 11b: Distal end area, 11c: Bottom area, 11d: Side area, 11e: First area, 11f: Second area, 11g: Third area, 11h: Heel, 11i: Main edge, 11j: Secondary edge, 12: Side notch, 12a: Bottom wall, 12b: Side wall, 12c: First area, 12d: Second area, 12e: Third area, 12f: Heel, 12g: Main edge, 12h: Secondary edge, 13A; 13B; 13C: Straight lamellar slot, 14A; 14B; 14C: Straight lamellar slot, 15A; 15B;15C: wavy lamellar slot, 21: non-continuous lamellar slot (continuous lamellar slot), 21A: shallow lamellar slot, 21a; 21c; 21e: deep area, 21b; 21d: shallow area, 21f; 21g; 21h: lamellar slot hull area, 21i: side wall, 21j: bottom wall, 21k: side wall, 22: compound lamellar slot (second lamellar slot), 22a: straight lamellar slot area, 22b: wavy lamellar slot area, 22c to 22g: area, 23: straight lamellar slot (first lamellar slot), 24: continuous projection area;

Claims

[1] Pneumatic tires (1), comprising: a central main groove (5) which is formed in a central zone of a tread area (2) in a tire width direction (TW) and extends in a tire circumferential direction (TC); a shoulder main groove (6, 6A, 6B) which is formed in the tread area (2) on one side of the ground contact end (GE, GE1, GE2) with respect to the central main groove (5) and extends in the tire circumferential direction (TC); a plurality of shoulder lateral grooves (8, 8A, 8B) extending in the tire width direction (TW), each shoulder lateral groove (8, 8A, 8B) having one end that communicates with the main shoulder groove (6, 6A, 6B) and another end that terminates outside a ground contact end (GE, GE1, GE2) in the tire width direction (TW), and wherein the shoulder lateral grooves (8, 8A, 8B) are spaced apart from each other in the tire circumferential direction (TC); and a shoulder block (9, 9A, 9B) bounded by the main shoulder groove (6, 6A, 6B) and two of the shoulder lateral grooves (8, 8A, 8B) adjacent to each other in the circumferential direction (TC), wherein The shoulder block (9, 9A, 9B) contains: the tread area (2), arranged inside the ground contact end (GE, GE1, GE2) in the tire width direction (TW), a side area (3) which is arranged outside the ground contact end (GE, GE1, GE2) in the tire width direction (TW) and extends in a tire radial direction, and a shoulder area (4) which is a curved area and connects the tread area (2) and the side area (3), a smooth zone (4a) which does not contain any depressions or protrusions, is provided in the shoulder block (9, 9A, 9B) in both lateral areas of the shoulder area (4) except for a central area of ​​the shoulder area (4) in the tire circumferential direction (TC), and a first lamellar slot (23) which reaches the smooth zone (4a) in the tire radial direction is provided in the side area (3), wherein the pneumatic tire (1) further comprises a second lamellar slot (22) which is arranged in the tread area (2) of the shoulder block, extends in the tire width direction (TW) and has one end that is connected to the main shoulder groove (6, 6A, 6B) and another end that reaches the smooth zone (4a), wherein the first louver slot (23) is provided at a point on an imaginary extension of the second louver slot (22), and the second lamellar slit (22) has a linear lamellar slit area (22a) connected to the main shoulder groove (6, 6A, 6B) and a wavy lamellar slit area (22b) extending to the smooth zone (4a). [2] Pneumatic tire (1) according to claim 1, wherein the first lamellar slot (23) is a linear lamellar slot (23). [3] Pneumatic tire (1) according to claim 1 or 2, further comprising a continuous lamellar slot (21) arranged in a central region of the shoulder block (9, 9A, 9B) in the circumferential direction (TC) of the tire and extending through the tread region (2), the shoulder region (4) and the side region (3), wherein the smooth zone (4a), the first lamellar slot (23) and the second lamellar slot (22) are each provided on both sides of the continuous lamellar slot (21) in the circumferential direction (TC).

Images