tire

Abstract

To provide a tire which may exhibit the excellent on-snow turning performance while maintaining the on-snow braking performance.SOLUTION: A tire includes a tread part 2 whose direction of attachment to a vehicle is designated. A middle land part 12 includes a plurality of middle blocks 24 sectioned into a plurality of middle lateral grooves 20. The middle lateral groove 20 includes a first groove part 21 and a second groove part 22. With a positional deviation of the second groove part 22 to one side in the tire circumferential direction with respect to the first groove part 21, the middle lateral groove 20 includes two vertical edges 25 extending along the tire circumferential direction between the edge of the first groove part 21 and the edge of the second groove part 22. The middle block 24 includes a break groove 26 extending from a first circumferential direction edge 24a and having a break end 26a in the middle block 24. The break end 26a of the break groove 26 is located on the first circumferential direction edge 24a side with respect to the two vertical edges 25.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a tire. [Background technology]

[0002] The following Patent Document 1 proposes a pneumatic tire having a plurality of shoulder lateral grooves in the shoulder land portion and a plurality of first middle lateral grooves in the first middle land portion. The shoulder lateral grooves and the first middle lateral grooves are expected to maintain the performance on icy roads and improve the performance on snow. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-013514 A Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, tires intended for use in winter have been required to have improved braking performance and turning performance on snow. Meanwhile, with the recent improvement in vehicle maneuverability, tires are required to have further improved turning performance on snow.

[0005] The present invention has been devised in view of the above circumstances, and has as its main object to provide a tire that can exhibit excellent cornering performance on snow while maintaining braking performance on snow. [Means for solving the problem]

[0006] The present invention relates to a tire having a tread portion, the tread portion including a first tread edge and a second tread edge, a plurality of circumferential grooves extending continuously in a tire circumferential direction between the first tread edge and the second tread edge, and a middle land portion arranged on the first tread edge side of the tire equator and divided into the circumferential grooves, the middle land portion including a plurality of middle blocks divided into a plurality of middle lateral grooves crossing the middle land portion, the middle lateral groove including a first groove portion extending in the tire axial direction on the first tread edge side and a second groove portion extending in the tire axial direction on the second tread edge side. , the second groove portion is shifted to one side in the tire circumferential direction relative to the first groove portion, so that the middle lateral groove includes a longitudinal edge extending along the tire circumferential direction between an edge of the first groove portion and an edge of the second groove portion, the middle block includes a first circumferential edge on the first tread end side and a second circumferential edge on the second tread end side, and the middle block is provided with an interrupted groove extending from the first circumferential edge and having an interrupted end within the middle block, and the interrupted end of the interrupted groove is located on the first circumferential edge side of the longitudinal edge.

[0007] In the tire of the present invention, the length of the vertical edge in the tire circumferential direction is desirably 40% to 60% of the groove width of the first groove portion.

[0008] In the tire of the present invention, the maximum depth of the middle lateral grooves is desirably 40% to 60% of the maximum depth of the circumferential grooves.

[0009] In the tire of the present invention, the length of the discontinuous groove in the axial direction of the tire is preferably 40% to 60% of the length of the first groove portion in the axial direction of the tire.

[0010] In the tire of the present invention, it is preferable that the middle block is provided with a sipe pair in which two sipes are adjacent to each other in the tire axial direction, and that the sipe pair includes a first middle sipe extending from the first circumferential edge and having an interrupted end within the middle block, and a second middle sipe extending from the second circumferential edge and having an interrupted end within the middle block.

[0011] In the tire of the present invention, the distance in the tire axial direction from the end of the first middle sipe to the end of the second middle sipe is preferably 3% to 7% of the maximum width in the tire axial direction of the middle block.

[0012] In the tire of the present invention, it is preferable that the discontinued end of the first middle sipe is located closer to the first circumferential edge than the longitudinal edge.

[0013] In the tire of the present invention, it is preferable that the middle block is provided with a third middle sipe extending from the second circumferential edge and having an interrupted end within the middle block on the first circumferential edge side of the longitudinal edge.

[0014] In the tire of the present invention, it is preferable that the longitudinal edges extend at an angle of 5° or less with respect to the tire circumferential direction.

[0015] In the tire of the present invention, it is preferable that the tread portion has a specified orientation for mounting on a vehicle, the first tread end is on the outer side of the vehicle when mounted on the vehicle, the tread portion includes an outer shoulder land portion adjacent to the first tread end side of the middle land portion via the circumferential groove, the outer shoulder land portion is provided with a plurality of outer shoulder lateral grooves crossing the outer shoulder land portion, and in a plan view of the tread, the axial inner end of the outer shoulder lateral groove overlaps with a projected area obtained by extending parallel to the axial direction of the tire axial outer end of the interrupted groove.

[0016] In the tire of the present invention, it is preferable that the tread portion has a specified orientation for mounting on a vehicle, the first tread end is on the outer side of the vehicle when mounted on the vehicle, the circumferential groove includes an outer crown circumferential groove adjacent to the second tread end side of the middle land portion, and the outer crown circumferential groove includes a plurality of variable width portions in the tire circumferential direction, the groove width of which gradually decreases toward one side in the tire circumferential direction. Effect of the Invention

[0017] By adopting the above-mentioned configuration, the tire of the present invention can exhibit excellent cornering performance on snow while maintaining braking performance on snow. [Brief description of the drawings]

[0018] [Figure 1] 1 is a development view of a tread portion of a tire according to one embodiment of the present invention. [Diagram 2] FIG. 2 is an enlarged view of the middle land area of ​​FIG. [Diagram 3] FIG. 3 is an enlarged view of a middle block and a middle lateral groove of FIG. 2. [Figure 4] FIG. 2 is an enlarged view of the inner middle land portion of FIG. [Diagram 5] FIG. 5 is an enlarged view of the lateral grooves and blocks of the inner middle land portion of FIG. 4. [Figure 6] 5 is a cross-sectional view taken along line AA in FIG. 4. [Figure 7] 6 is a cross-sectional view taken along line BB in FIG. 5. [Figure 8] 6 is a cross-sectional view taken along line CC in FIG. 5. [Figure 9] FIG. 2 is an enlarged view of the outer shoulder land portion of FIG. [Figure 10] FIG. 2 is an enlarged view of the inner shoulder land portion of FIG. [Figure 11] FIG. 2 is an enlarged view of the crown land portion of FIG. [Figure 12] FIG. 4 is an enlarged view of a middle land portion of a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a development view of a tread portion 2 of a tire 1 of this embodiment. As shown in Fig. 1, the tire 1 of this embodiment is used, for example, as a pneumatic tire for passenger cars intended for use in winter. However, the tire 1 of the present invention is not limited to such an embodiment.

[0020] The tire 1 of this embodiment has a tread portion 2 for which the mounting orientation on a vehicle is specified, for example. The mounting orientation on a vehicle is indicated, for example, by letters or marks on the sidewall portion or the like (not shown). The tread portion 2 is configured, for example, in an asymmetric pattern (meaning that the tread pattern is not line-symmetric with respect to the tire equator C). However, the tire 1 of the present invention is not limited to this embodiment, and may be one for which the mounting orientation on a vehicle is not specified.

[0021] The tread portion 2 includes a first tread edge T1 and a second tread edge T2. In this embodiment, the first tread edge T1 is on the outer side of the vehicle when mounted on the vehicle, and the second tread edge T2 is on the inner side of the vehicle when mounted on the vehicle. The first tread edge T1 and the second tread edge T2 each correspond to the axially outermost contact positions when the tire 1 in a normal state is loaded with a normal load and contacts a flat surface with a camber angle of 0°.

[0022] "Normal condition" means, in the case of a pneumatic tire for which various standards are established, that the tire is mounted on a normal rim, inflated to the normal internal pressure, and no load is applied. In the case of a tire for which various standards are not established or a non-pneumatic tire, the normal condition means a standard use condition according to the intended use of the tire, and a state in which no load is applied. In this specification, unless otherwise specified, the dimensions of each part of the tire are values ​​measured in the normal condition.

[0023] A "genuine rim" is a rim that is defined for each tire by the standard system that includes the standard on which the tire is based. For example, in the case of JATMA, it is called a "standard rim," in the case of TRA, it is called a "Design Rim," and in the case of ETRTO, it is called a "Measuring Rim."

[0024] "Normal internal pressure" is the air pressure set for each tire by each standard in the standard system on which the tire 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 AT VARIOUS COLD INFLATION PRESSURES." In the case of ETRTO, it is the "INFLATION PRESSURE."

[0025] In the case of a pneumatic tire for which various standards are established, the "normal load" is the load that each standard specifies for each tire in the standard system including the standard on which the tire is based. For JATMA, it is the "maximum load capacity", for TRA, it is the maximum value listed in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES", and for ETRTO, it is the "LOAD CAPACITY". In addition, in the case of a tire for which various standards are not established or a non-pneumatic tire, the "normal load" refers to the load acting on one tire in the standard mounting state of the tire. The "standard mounting state" refers to a state in which the tire is mounted on a standard vehicle according to the intended use of the tire, and the vehicle is stationary on a flat road surface in a drivable state.

[0026] The tread portion 2 includes a plurality of circumferential grooves 3 extending continuously in the tire circumferential direction between the first tread edge T1 and the second tread edge T2, and a plurality of land portions divided by the circumferential grooves 3. The tire 1 of this embodiment is configured as a so-called five-rib tire in which the tread portion 2 includes five land portions divided by four circumferential grooves 3. However, the present invention is not limited to this embodiment, and for example, the tire may be a so-called four-rib tire in which the tread portion 2 is configured by three circumferential grooves 3 and four land portions.

[0027] The circumferential grooves 3 include, for example, an outer crown circumferential groove 5, an outer shoulder circumferential groove 4, an inner crown circumferential groove 6, and an inner shoulder circumferential groove 7. The outer crown circumferential groove 5 is provided between the tire equator C and the first tread edge T1. The outer shoulder circumferential groove 4 is provided between the outer crown circumferential groove 5 and the first tread edge T1. The inner crown circumferential groove 6 is provided between the tire equator C and the second tread edge T2. The inner shoulder circumferential groove 7 is provided between the inner crown circumferential groove 6 and the second tread edge T2.

[0028] The circumferential grooves 3 may have various configurations, such as a configuration extending linearly in the tire circumferential direction, a configuration extending in a zigzag pattern, etc. Specific configurations of this embodiment will be described later.

[0029] The axial distance L1 from the groove centerline of the outer shoulder circumferential groove 4 or the inner shoulder circumferential groove 7 to the tire equator C is, for example, 20% to 35% of the tread width TW. The axial distance L2 from the groove centerline of the outer crown circumferential groove 5 or the inner crown circumferential groove 6 to the tire equator C is, for example, 3% to 15% of the tread width TW. The tread width TW is the axial distance from the first tread edge T1 to the second tread edge T2 in the normal state.

[0030] The groove width W1 of the circumferential groove 3 is desirably at least 3 mm. In a preferred embodiment, the groove width W1 of the circumferential groove 3 is 2.0% to 6.0% of the tread width TW. In this embodiment, of the four circumferential grooves 3, the inner crown circumferential groove 6 has the largest groove width.

[0031] The land portion includes a middle land portion 12 divided into circumferential grooves 3. The middle land portion 12 is divided, for example, between an outer shoulder circumferential groove 4 and an outer crown circumferential groove 5. As a result, the middle land portion 12 is located on the outer side of the tire equator when mounted on a vehicle. However, when the present invention is applied to a tire whose mounting orientation on a vehicle is not specified, the middle land portion 12 is not limited to the above-mentioned position.

[0032] Furthermore, the land portion of this embodiment includes an outer shoulder land portion 11, a crown land portion 13, an inner middle land portion 14, and an inner shoulder land portion 15. The outer shoulder land portion 11 is located axially outward of the outer shoulder circumferential groove 4, and includes a first tread edge T1. The crown land portion 13 is located between the outer crown circumferential groove 5 and the inner crown circumferential groove 6. The inner middle land portion 14 is located between the inner shoulder circumferential groove 7 and the inner crown circumferential groove 6. The inner shoulder land portion 15 is located axially outward of the inner shoulder circumferential groove 7, and includes a second tread edge T2.

[0033] Fig. 2 shows an enlarged view of the middle land portion 12. As shown in Fig. 2, the middle land portion 12 includes a plurality of middle blocks 24 that are divided into a plurality of middle lateral grooves 20 that cross the middle land portion 12 in the tire axial direction.

[0034] Fig. 3 shows an enlarged view of the middle lateral groove 20 and the middle block 24. As shown in Fig. 3, the middle lateral groove 20 includes a first groove portion 21 extending in the tire axial direction on the first tread edge T1 side, and a second groove portion 22 extending in the tire axial direction on the second tread edge T2 side. In addition, the second groove portion 22 is shifted to one side in the tire circumferential direction with respect to the first groove portion 21, so that the middle lateral groove 20 includes a longitudinal edge 25 extending in the tire circumferential direction between an edge 21a of the first groove portion 21 and an edge 22a of the second groove portion 22.

[0035] The middle block 24 includes a first circumferential edge 24a on the first tread edge T1 side and a second circumferential edge 24b on the second tread edge T2 side. The middle block 24 is provided with an interrupted groove 26 that extends from the first circumferential edge 24a and has an interrupted end 26a within the middle block 24. In the present invention, the interrupted end 26a of the interrupted groove 26 is located closer to the first circumferential edge 24a than the longitudinal edge 25. By adopting the above-mentioned configuration, the tire 1 of the present invention can exhibit excellent cornering performance on snow while maintaining braking performance on snow. The following mechanism is presumed to be the reason for this.

[0036] Since a large ground pressure acts on the middle land portion 12 during cornering, each groove arranged in the middle land portion 12 contributes greatly to on-snow performance. For this reason, the grooves arranged in the middle land portion 12 are specified in the present invention.

[0037] When driving on snow, the middle lateral grooves 20 compact the snow inside to form snow pillars, which are then sheared to generate a reaction force (hereinafter, such a reaction force may be referred to as snow pillar shear force), thereby improving braking performance on snow. In addition, since the middle lateral grooves 20 include the above-mentioned longitudinal edges 25, a large snow pillar shear force is also generated in the axial direction of the tire, thereby improving cornering performance on snow.

[0038] In addition, the discontinuous groove 26 also cooperates with the outer shoulder circumferential groove 4 to exert a large snow column shear force when traveling on snow, improving braking performance and cornering performance on snow.

[0039] Furthermore, in the present invention, since the interrupted groove 26 is interrupted closer to the first circumferential edge 24a than the longitudinal edge 25, the block piece 27 between the interrupted groove 26 and the first groove portion 21 is easily bent in the tire circumferential direction with the two longitudinal edges 25 of the middle lateral groove 20 as the fulcrum. This makes it easier for the first groove portion 21 to open and close depending on the change in ground pressure acting on the middle block. This action can prevent snow from clogging near the two longitudinal edges 25, and can continuously provide excellent turning performance on snow. It is presumed that this mechanism allows the present invention to provide excellent turning performance on snow while maintaining braking performance on snow.

[0040] A more detailed configuration of this embodiment will be described below. Each configuration described below shows a specific aspect of this embodiment. Therefore, it goes without saying that the present invention can achieve the above-mentioned effects even if it does not have the configuration described below. In addition, even if any one of the configurations described below is applied alone to the tire of the present invention having the above-mentioned characteristics, an improvement in performance according to each configuration can be expected. Furthermore, when some of the configurations described below are applied in combination, a composite improvement in performance according to each configuration can be expected.

[0041] As shown in FIG. 1, the outer shoulder circumferential groove 4 extends linearly with a constant groove width. On the other hand, the outer crown circumferential groove 5 includes multiple width-varying portions 5a in the tire circumferential direction, in which the groove width gradually decreases toward one side in the tire circumferential direction. Similarly, the inner crown circumferential groove 6 also includes multiple width-varying portions 6a in the tire circumferential direction, in which the groove width gradually decreases toward one side in the tire circumferential direction. The inner shoulder circumferential groove 7 also includes multiple width-varying portions 7a in the tire circumferential direction, in which the groove width gradually decreases toward one side in the tire circumferential direction. The circumferential groove 3 including the width-varying portions can strongly compact snow inside, which helps improve turning performance on snow.

[0042] In a preferred embodiment, the width-changing portion 5a of the outer crown circumferential groove 5 gradually decreases in width toward the first tire circumferential direction (upward in each drawing of this specification). The width-changing portion 6a of the inner crown circumferential groove 6 and the width-changing portion 7a of the inner shoulder circumferential groove 7 gradually decrease in width toward the second tire circumferential direction (downward in each drawing of this specification), which is opposite to the first tire circumferential direction. Such an arrangement of the width-changing portions allows solid snow pillars to form in the circumferential grooves 3 during both acceleration and deceleration.

[0043] As shown in Fig. 3, the middle lateral grooves 20 are inclined in a first direction (upward to the right in each drawing in this specification) with respect to the tire axial direction. The angle of the middle lateral grooves 20 with respect to the tire axial direction (the angle between the first groove portion 21 and the second groove portion 22) is, for example, 45° or less, and preferably 15 to 25°. Such middle lateral grooves 20 are useful for improving not only braking performance on snow but also cornering performance on snow.

[0044] The groove width W3 of the middle lateral grooves 20 is, for example, 15% to 25% of the maximum axial width W2 of the middle block 24. In this embodiment, the groove width of the first groove portion 21 is the same as the groove width of the second groove portion 22. The maximum depth of the middle lateral grooves 20 is 40% to 60% of the maximum depth of the circumferential grooves 3. Such middle lateral grooves 20 improve the on-snow performance and the steering stability on dry roads (hereinafter may be simply referred to as steering stability) in a well-balanced manner.

[0045] The axial length L3 of the first groove portion 21 is preferably 30% or more, more preferably 40% or more, and preferably 70% or less, more preferably 60% or less of the width W2 of the middle block 24. The axial length of the second groove portion 22 is also preferably limited to the range of the length L3 of the first groove portion 21 described above.

[0046] The two longitudinal edges 25 are preferably included in the central portion when the middle block 24 is divided into three equal parts in the axial direction by an imaginary plane extending parallel to the tire circumferential direction. The angle of the longitudinal edges 25 with respect to the tire circumferential direction is, for example, 10° or less, and preferably 5° or less. As a more preferable aspect, the longitudinal edges 25 of this embodiment are arranged parallel to the tire circumferential direction. Such longitudinal edges 25 provide a large reaction force in the axial direction of the tire when traveling on snow, and reliably improve cornering performance on snow.

[0047] In order to form a solid snow pillar in the middle lateral groove 20, it is desirable that the distance between the two longitudinal edges 25 in the tire axial direction is small. For this reason, the distance between the two longitudinal edges 25 in the tire axial direction is desirably 10 mm or less, and more desirably 5 mm or less. In this embodiment, the distance is substantially zero. Therefore, in a plan view of the tread, the two longitudinal edges 25 are located on the same straight line.

[0048] The circumferential length L4 of one longitudinal edge 25 is preferably 30% or more, more preferably 40% or more, and preferably 70% or less, more preferably 60% or less of the groove width W3a of the first groove portion 21. Such a longitudinal edge 25 can achieve the above-mentioned effects while maintaining the drainage performance of the middle lateral grooves 20.

[0049] The discontinuous groove 26 has a groove width that gradually decreases from the outer shoulder circumferential groove 4 toward the discontinuous end 26a. The maximum groove width W4 of the discontinuous groove 26 is smaller than the groove width W3 of the middle lateral groove 20. Specifically, the groove width W4 of the discontinuous groove 26 is 60% to 90% of the groove width W3 of the middle lateral groove 20. Such a discontinuous groove 26 is useful for improving on-snow performance and steering stability in a well-balanced manner.

[0050] The discontinuous grooves 26 are inclined, for example, in the first direction. The angle of the discontinuous grooves 26 with respect to the tire axial direction is, for example, 45° or less, and preferably 10 to 25°.

[0051] The axial length L5 of the interrupted groove 26 is preferably 30% or more, more preferably 40% or more, and preferably 70% or less, more preferably 30% or less, of the axial length L3 of the first groove portion 21.

[0052] 2, the middle block 24 is provided with a plurality of middle sipes 30. The middle sipes 30 are inclined, for example, in the first direction. The angle of the middle sipes 30 with respect to the tire axial direction is, for example, 15 to 25 degrees. When the sipes extend in a wavy shape, the angle refers to the angle of an imaginary line connecting both ends of the sipe with respect to the tire axial direction.

[0053] In this specification, the term "sipe" refers to a cut element having a minute width, and the width between two opposing sipe walls is 0.6 mm or less. The width of the sipe is preferably 0.1 to 0.5 mm, and more preferably 0.2 to 0.4 mm. The sipe of this embodiment has the width in the above-mentioned range over its entire depth. The sipe may be connected to a chamfered opening or a flask bottom having a width larger than the above-mentioned range.

[0054] Each sipe in this embodiment extends, for example, in a wavy manner in a plan view of the tread. In this case, the peak-to-peak amplitude of the sipe is preferably 0.80 to 1.20 mm. Also, the wavelength of the sipe is preferably 2.0 to 5.0 mm. However, the present invention is not limited to such an embodiment, and each sipe may extend linearly. Also, in a preferred embodiment, each sipe is configured as a so-called 3D sipe that extends in a wavy manner in its cross section. Such sipes are useful for maintaining the rigidity of the land portion when the sipe walls facing each other contact each other, and are useful for improving the steering stability on dry road surfaces.

[0055] At least one of the middle sipes 30 extends from the first circumferential edge 24a or the second circumferential edge 24b and has an interrupted end within the middle block 24. Such middle sipes 30 can improve braking performance on snow while maintaining the rigidity of the middle block 24.

[0056] In this embodiment, the middle block 24 is provided with a sipe pair 29 in which two sipes are adjacent to each other in the tire axial direction. This sipe pair 29 includes a first middle sipe 31 and a second middle sipe 32. The first middle sipe 31 extends from the first circumferential edge 24a and has an interrupted end 31a in the middle block 24. The interrupted end 31a is located, for example, closer to the first circumferential edge 24a than the longitudinal edge 25. The second middle sipe 32 extends from the second circumferential edge 24b and has an interrupted end 32a in the middle block 24. Such a sipe pair 29 is also useful for improving braking performance on ice.

[0057] A distance L6 (shown in FIG. 3) in the tire axial direction from the end 31a of the first middle sipe 31 to the end 32a of the second middle sipe 32 is 3% to 7% of the maximum axial width W2 of the middle block 24. Such a sipe pair 29 can ensure a sufficient sipe length while maintaining the rigidity of the middle block 24.

[0058] The middle block 24 is provided with a third middle sipe 33. The third middle sipe 33 extends from the second circumferential edge 24b and has an interrupted end 33a within the middle block 24 on the first circumferential edge 24a side of the two longitudinal edges 25. The axial length of the third middle sipe 33 is, for example, 60% to 80% of the width W2 of the middle block 24. Such third middle sipes 33 are useful for improving performance on ice and on snow.

[0059] The maximum depth of the third middle sipes 33 is greater than the maximum depth of the first middle sipes 31 and greater than the maximum depth of the second middle sipes 32. The maximum depth of the third middle sipes 33 is, for example, 130% to 150% of the maximum depth of the first middle sipes 31 or the second middle sipes 32. Such third middle sipes 33 open more easily than the first middle sipes 31 and the second middle sipes 32, further improving performance on ice.

[0060] In this embodiment, the middle block 24 is provided with a dimple 34 between the first groove portion 21 and the interrupted groove 26. The dimple 34 is recessed in an area surrounded by an edge of an ellipse that is elongated in the circumferential direction of the tire. Such a dimple 34 moderately reduces the rigidity of the middle block 24 and helps to prevent snow from clogging the middle lateral grooves 20 and the interrupted grooves 26.

[0061] 4 shows an enlarged view of the inner middle land portion 14. As shown in FIG. 4, the inner middle land portion 14 includes a plurality of blocks 36 separated by a plurality of lateral grooves 35.

[0062] Fig. 5 shows an enlarged view of the lateral groove 35 and the block 36 of the inner middle land portion 14. As shown in Fig. 5, the block 36 includes an outer circumferential edge 36a and an inner circumferential edge 36b arranged on both sides of the tread surface, one lateral narrow groove 38 extending from the outer circumferential edge 36a to the inner circumferential edge 36b with a groove width smaller than that of the lateral groove 35, and a plurality of lateral sipes 40 with a width of 0.6 mm or less. In the block 36 of this embodiment, the outer circumferential edge 36a is located closer to the tire equator C than the inner circumferential edge 36b.

[0063] The width W5 of the lateral narrow groove 38 is 1.0 to 2.0 mm. The maximum depth of the lateral narrow groove 38 is 40% to 60% of the maximum depth of the lateral groove 35.

[0064] The lateral sipes 40 include full-open sipes 41 extending from the outer circumferential edge 36a to the inner circumferential edge 36b, and semi-open sipes 42 extending from the outer circumferential edge 36a or the inner circumferential edge 36b and having an interrupted end 42a within the block 36.

[0065] 6 shows a cross-sectional view of line AA in FIG. 4. As shown in FIG. 6, the maximum depth d3 of the full-open sipe 41 is greater than the maximum depth d2 of the lateral narrow groove 38 and is smaller than the maximum depth d1 of the lateral groove 35. Similarly, the maximum depth d4 of the semi-open sipe 42 is greater than the maximum depth d2 of the lateral narrow groove 38 and is smaller than the maximum depth d1 of the lateral groove 35. In this embodiment, the configuration of the blocks 36 of the inner middle land portion 14 can improve the performance on snow and the steering stability on dry roads while maintaining the performance on ice. The following mechanism is presumed to be the reason for this.

[0066] As shown in Fig. 4, the lateral grooves 35 and the circumferential grooves 3 communicating with them can form hard snow columns, which helps to improve performance on snow. In addition, the lateral narrow grooves 38, which have a groove width of 1.0 to 2.0 mm and a depth of 40% to 60% of the lateral grooves 35, can form snow columns while minimizing the decrease in rigidity of the blocks 36, providing snow column shear force. This improves performance on snow and steering stability on dry roads.

[0067] On the other hand, the full-open sipes 41 and the semi-open sipes 42 provide an edge component and maintain on-ice performance. In particular, the semi-open sipes 42 provide an edge component while maintaining the rigidity of the blocks 36, thereby improving on-ice performance and steering stability in a well-balanced manner.

[0068] As shown in FIG. 6, by specifying the depth of the full-open sipe 41 and the semi-open sipe 42 as described above, the rigidity of the block 36 is maintained, and the block piece 37 between the lateral groove 35 and the lateral narrow groove 38 is easily collapsed toward the lateral groove 35. This makes it easier for the lateral narrow groove 38 to open and close due to changes in ground pressure. Due to this action, even if the lateral narrow groove 38 has a small groove width, a solid snow pillar can be formed, and the snow pillar can be prevented from clogging in the groove, improving the performance on snow. In this embodiment, it is presumed that this mechanism can improve the performance on snow and the steering stability on dry roads while maintaining the performance on ice.

[0069] 5, the lateral grooves 35 extend linearly and inclined in the first direction. The angle of the lateral grooves 35 with respect to the axial direction of the tire is, for example, 15 to 25°.

[0070] The maximum depth of the lateral grooves 35 is, for example, greater than the maximum depth of the middle lateral grooves 20. The depth of the lateral grooves 35 is, for example, 80% to 120% of the maximum depth of the circumferential grooves 3. In this embodiment, the depth of the lateral grooves 35 and the depth of the circumferential grooves 3 are the same.

[0071] The lateral narrow groove 38 extends linearly, for example, inclined in the first direction. The angle of the lateral narrow groove 38 with respect to the tire axial direction is, for example, 15 to 25°. In a desirable embodiment, the angle difference between the lateral groove 35 and the lateral narrow groove 38 is 5° or less, and in this embodiment, they are parallel. Such a lateral narrow groove 38 improves the braking performance and cornering performance on ice and snow in a well-balanced manner.

[0072] As shown in FIG. 4, the multiple blocks 36 include a first block piece 43 and a second block piece 44 divided by a lateral narrow groove 38. In addition, in at least one of the multiple blocks 36, the first block piece 43 and the second block piece 44 have substantially the same length in the tire circumferential direction. "Substantially the same" includes an embodiment in which the length in the tire circumferential direction of the first block piece 43 is 90% to 110% of the length in the tire circumferential direction of the second block piece 44. Hereinafter, such a block may be referred to as an equal block 46. The block 36 shown in FIG. 5 is an equal block 46.

[0073] In the equal-division block 46, one full-open sipe 41 and one semi-open sipe 42 are provided in each of the first block piece 43 and the second block piece 44. In this case, the full-open sipe 41 is provided adjacent to the lateral narrow groove 38. The semi-open sipe 42 is provided between the lateral groove 35 and the full-open sipe 41.

[0074] In at least one of the multiple blocks 36, the length of the first block piece 43 in the tire circumferential direction is different from the length of the second block piece 44 in the tire circumferential direction. Hereinafter, such a block may be referred to as an unequal block 47. In the unequal block 47 of this embodiment, the length of the second block piece 44 in the tire circumferential direction is, for example, about 50% to 80% of the length of the first block piece 43 in the tire circumferential direction.

[0075] In the unequal block 47 of the present embodiment, one full-open sipe 41 and one semi-open sipe 42 are provided in the first block piece 43. In the first block piece 43, the full-open sipe 41 is provided adjacent to the lateral narrow groove 38. The semi-open sipe 42 is provided between the lateral groove 35 and the full-open sipe 41.

[0076] The second block piece 44 of the unequal block 47 is provided with only one semi-open sipe 42 .

[0077] In this embodiment, since the inner middle land portion 14 includes a plurality of the above-mentioned equal blocks 46 and unequal blocks 47, the impact sound when the inner middle land portion 14 touches the ground is turned into white noise, thereby achieving excellent noise performance.

[0078] The full-open sipes 41 and the semi-open sipes 42 are inclined, for example, in the first direction. The angle of the full-open sipes 41 and the semi-open sipes 42 with respect to the tire axial direction is, for example, 15 to 25 degrees.

[0079] 6, the maximum depth d3 of the full-open sipe 41 is 70% to 90% of the maximum depth d1 of the lateral groove 35. Such a full-open sipe 41 helps to improve on-ice performance while maintaining the rigidity of the block 36.

[0080] FIG. 7 shows a cross-sectional view of line BB in FIG. 5. As shown in FIG. 7, the full open sipe 41 includes a shallow bottom portion 41a whose bottom portion is raised at the end portion on the inner shoulder circumferential groove 7 side. The depth d5 ​​of the shallow bottom portion 41a is 30% to 40% of the maximum depth d3 of the full open sipe 41. Such a full open sipe 41 can improve the performance on ice while maintaining the rigidity of the block 36. Note that each sipe of this embodiment is configured as a 3D sipe, so that the sipe wall has irregularities, but the irregularities are omitted in each drawing showing the sipe wall such as FIG. 7 in this specification.

[0081] 4, in this embodiment, the outer circumferential edge 36a is located closer to the tire equator C than the inner circumferential edge 36b, and each semi-open sipe 42 communicates with the outer circumferential edge 36a. This makes it easier for the semi-open sipes 42 to open on the tire equator C side, and prevents snow from clogging the inner crown circumferential groove 6.

[0082] The semi-open sipe 42 crosses, for example, the axial center position of the block 36. The length of the semi-open sipe 42 in the axial direction of the tire is, for example, 70% to 95% of the maximum width of the block 36 in the axial direction of the tire.

[0083] 6, the maximum depth d4 of the semi-open sipe 42 is smaller than the maximum depth d3 of the full-open sipe 41. The depth d4 of the semi-open sipe 42 is, for example, 50% to 65% of the maximum depth d1 of the lateral groove 35. Such a semi-open sipe 42 can improve on-ice performance while maintaining the rigidity of the block 36.

[0084] 8 shows a cross-sectional view of line CC in FIG. 5. As shown in FIG. 8, the semi-open sipe 42 includes a shallow bottom portion 42b with a raised bottom portion on the side of the broken end 42a. In a more preferable embodiment, the semi-open sipe 42 includes a central shallow bottom portion 42c with a raised bottom portion on the outer circumferential edge 36a side than the shallow bottom portion 42b. Such a semi-open sipe 42 can more reliably maintain the rigidity of the block 36, and exhibits excellent driving stability.

[0085] 5, the block 36 of the present embodiment is provided with a dimple 48 between the semi-open sipe 42 and the inner shoulder circumferential groove 7. The dimple 48 is recessed in an area surrounded by an edge of an ellipse that is elongated in the tire circumferential direction. Such a dimple 48 can moderately reduce the rigidity of the block 36 and prevent snow from clogging the surrounding grooves.

[0086] 9 shows an enlarged view of the outer shoulder land portion 11. As shown in FIG. 9, the outer shoulder land portion 11 includes, for example, a plurality of outer shoulder blocks 51 separated by a plurality of outer shoulder lateral grooves 50.

[0087] The outer shoulder lateral groove 50 includes, for example, an inner groove portion 50a and an outer groove portion 50b. The inner groove portion 50a, for example, communicates with the outer shoulder circumferential groove 4 and is inclined in the first direction. The outer groove portion 50b, for example, communicates with the first tread edge T1 side of the inner groove portion 50a and is inclined in a second direction opposite to the first direction with respect to the tire axial direction. The outer shoulder lateral groove 50 including such an inner groove portion 50a and outer groove portion 50b improves snow braking performance and snow cornering performance in a well-balanced manner.

[0088] The angle of the inner groove portion 50a with respect to the tire axial direction is, for example, 5 to 15°. The angle of the outer groove portion 50b with respect to the tire axial direction is, for example, 5 to 15°. The outer groove portion 50b crosses the axial center position of the outer shoulder land portion 11. The axial length L7 of the outer groove portion 50b is, for example, 60% to 80% of the axial width W6 of the outer shoulder land portion 11.

[0089] In a plan view of the tread, the axially inner end 50c of the outer shoulder lateral groove 50 overlaps with a projected area obtained by extending parallel to the axial direction the axially outer end 26b of the interrupted groove 26. Such outer shoulder lateral groove 50 cooperates with the interrupted groove 26 to form solid snow pillars, further improving on-snow performance.

[0090] The outer shoulder block 51 is provided with a plurality of first outer shoulder sipes 53 and a plurality of second outer shoulder sipes 54. The first outer shoulder sipes 53 in this embodiment, for example, communicate with the outer shoulder circumferential groove 4 and terminate within the outer shoulder block 51. The second outer shoulder sipes 54 are provided, for example, axially outward of the first outer shoulder sipe 53 and terminate at both ends within the outer shoulder block 51. Such first outer shoulder sipes 53 and second outer shoulder sipes 54 improve steering stability on dry roads and performance on ice in a well-balanced manner.

[0091] In a more preferable embodiment, in one outer shoulder block 51, the number of the second outer shoulder sipes 54 is preferably less than the number of the first outer shoulder sipes 53. Such an arrangement of the sipes helps to suppress uneven wear in the vicinity of the first tread edge T1.

[0092] Fig. 10 shows an enlarged view of the inner shoulder land portion 15. As shown in Fig. 10, the inner shoulder land portion 15 is provided with a plurality of inner shoulder lateral grooves 55 and a plurality of inner shoulder interrupted grooves 56.

[0093] The inner shoulder lateral groove 55 crosses, for example, the inner shoulder land portion 15 in the tire axial direction. The inner shoulder lateral groove 55 of the present embodiment includes, for example, a first inclined groove portion 55a extending from the inner shoulder circumferential groove 7 at an incline in the first direction, and a second inclined groove portion 55b continuing to the first inclined groove portion 55a and extending at an incline in the second direction. Such an inner shoulder lateral groove 55 improves the braking performance on snow and the cornering performance on snow in a well-balanced manner.

[0094] It is desirable that the length L8 of the first inclined groove portion 55a in the tire axial direction is, for example, 20% to 50% of the width W7 of the inner shoulder land portion 15 in the tire axial direction.

[0095] In a plan view of the tread, it is desirable that the axially inner end portion 55c of the inner shoulder lateral groove 55 overlaps with an area obtained by extending the lateral narrow groove 38 provided in the inner middle land portion 14 along its length. Such an inner shoulder lateral groove 55 cooperates with the lateral narrow groove 38 to form a hard snow column, improving on-snow performance.

[0096] The inner shoulder interrupted groove 56 communicates with the inner shoulder circumferential groove 7 and has an interrupted end 56a within the inner shoulder land portion 15. The inner shoulder interrupted groove 56 of this embodiment includes a portion extending along the first inclined groove portion 55a and a portion extending along the second inclined groove portion 55b. Such an inner shoulder interrupted groove 56 suppresses uneven wear of the inner shoulder land portion 15 while improving performance on snow and performance on ice.

[0097] In a plan view of the tread, it is preferable that an axially inner end portion 56b of the inner shoulder-discontinuous groove 56 overlaps with a region obtained by extending the lateral groove 35 provided in the inner middle land portion 14 along its length direction.

[0098] The inner shoulder land portion 15 includes a plurality of inner shoulder blocks 57 that are divided into a plurality of inner shoulder lateral grooves 55. The inner shoulder block 57 is provided with a first inner shoulder sipe 58 and a second inner shoulder sipe 59.

[0099] The first inner shoulder sipe 58 of the present embodiment, for example, communicates with the inner shoulder circumferential groove 7 and terminates within the inner shoulder block 57. The second inner shoulder sipe 59 is provided, for example, axially outward of the first inner shoulder sipe 58, and both ends terminate within the inner shoulder block 57. Such first inner shoulder sipe 58 and second inner shoulder sipe 59 can improve on-ice performance while maintaining the rigidity of the inner shoulder block 57.

[0100] 11 shows an enlarged view of the crown land portion 13. As shown in FIG. 11, the crown land portion 13 includes a plurality of crown blocks 61 separated by a plurality of crown lateral grooves 60.

[0101] The crown lateral grooves 60 cross the crown land portion 13 in the tire axial direction. The crown lateral grooves 60 of this embodiment include, for example, a first crown groove portion 60a and a second crown groove portion 60b. The first crown groove portion 60a communicates with, for example, the outer crown circumferential groove 5 and is inclined in the first direction. The second crown groove portion 60b communicates with, for example, the inner crown circumferential groove 6 and is inclined in the second direction. Such crown lateral grooves 60 can strongly compact snow therein, further improving braking performance on snow.

[0102] An outer end portion of the first crown groove portion 60a on the first tread edge T1 side overlaps, for example, with a region obtained by extending the second groove portion 22 of the middle lateral groove 20 along its length direction. An outer end portion 64 of the second crown groove portion 60b on the second tread edge T2 side overlaps, for example, with a region obtained by extending, in parallel to the tire axial direction, an end portion of the lateral groove 35 on the inner middle land portion 14 on the inner crown circumferential groove 6 side.

[0103] The crown block 61 is provided with a first crown-interrupted groove 62 and a second crown-interrupted groove 63. The first crown-interrupted groove 62 extends, for example, from the crown lateral groove 60 and terminates within the crown block 61. The second crown-interrupted groove 63 extends from the inner crown circumferential groove 6 and terminates within the crown block 61. Such first crown-interrupted groove 62 and second crown-interrupted groove 63 can moderately reduce the rigidity of the crown block 61 and suppress snow from clogging the crown lateral groove 60 and the inner crown circumferential groove 6.

[0104] The crown block 61 is provided with a plurality of crown sipes 65. The crown sipes 65 are inclined, for example, in the second direction.

[0105] As shown in Fig. 1, the land ratio of the tread portion 2 is desirably, for example, 60% to 75%. In this specification, the land ratio means the ratio of the total area of ​​the actual contact surface of the tread portion 2 to the total area of ​​the virtual contact surface in which all the grooves of the tread portion are filled. Such a tread portion 2 improves the performance on snow and the handling stability while maintaining the performance on ice.

[0106] From the same viewpoint, the rubber hardness of the tread rubber constituting the tread portion 2 is, for example, 45 to 65°. Here, the rubber hardness refers to a durometer A hardness measured in an environment of 23° C. by a durometer type A based on JIS-K6253.

[0107] Although the tire according to one embodiment of the present invention has been described in detail above, the present invention is not limited to the above specific embodiment and can be modified and carried out in various aspects. EXAMPLES

[0108] A tire having a size of 195 / 65R15 and the basic tread pattern of FIG. 1 was prototyped based on the specifications of Tables 1-2. As a comparative example, a tire having a middle land portion a shown in FIG. 12 was prototyped. As shown in FIG. 12, the middle land portion a of the comparative example is provided with a plurality of middle lateral grooves b extending linearly. The middle lateral groove b of the comparative example does not have the first groove portion and the second groove portion of the present invention, and the two edges extend linearly. The comparative example tire has substantially the same pattern as that shown in FIG. 1, except for the above-mentioned configuration. Each test tire was tested for braking performance on snow and cornering performance on snow. The common specifications and test method of each test tire are as follows. Rim: 15×6.0JJ Tire pressure: front wheel 200kPa, rear wheel 200kPa Test vehicle: 1500cc, front-wheel drive Tire mounting position: All wheels

[0109] <Snow braking performance> The braking performance of the test vehicle when it was driven on snow was evaluated by the driver. The results are given as a score based on the comparative example being 100, with a higher score indicating better braking performance on snow.

[0110] <Turning performance on snow> The cornering performance of the test vehicle on snow was evaluated by the driver. The results are given as a score based on the comparative example being 100, with a higher score indicating better cornering performance on snow. The test results are shown in Tables 1-2.

[0111] [Table 1]

[0112] [Table 2]

[0113] As shown in Table 1, it was confirmed that the tire of the present invention exhibits excellent cornering performance on snow while maintaining braking performance on snow. [Explanation of symbols]

[0114] 2 Tread section 12 Middle Land Section 20 Middle Yokomizo 21 First groove 22 Second groove 24 Middle Block 24a 1st circumferential edge 24b Second circumferential edge 25 Vertical Edge 26a End 26 Broken Groove T1 First tread edge T2 Second tread edge

Claims

1. A tire having a tread portion, the tread portion includes a first tread edge and a second tread edge, a plurality of circumferential grooves extending continuously in a tire circumferential direction between the first tread edge and the second tread edge, and a middle land portion disposed on the first tread edge side relative to a tire equator and divided by the circumferential grooves, The middle land portion includes a plurality of middle blocks divided into a plurality of middle lateral grooves crossing the middle land portion, The middle lateral groove includes a first groove portion extending in the tire axial direction at the first tread end side and a second groove portion extending in the tire axial direction at the second tread end side, the second groove portion is offset from the first groove portion to one side in the tire circumferential direction, so that the middle lateral groove includes a longitudinal edge extending in the tire circumferential direction between an edge of the first groove portion and an edge of the second groove portion, the middle block includes a first circumferential edge on the first tread end side and a second circumferential edge on the second tread end side, The middle block is provided with an interrupted groove extending from the first circumferential edge and having an interrupted end within the middle block, The interrupted end of the interrupted groove is located closer to the first circumferential edge than the longitudinal edge, The tread portion has a specified orientation for mounting on a vehicle, The first tread edge is on the outer side of the vehicle when the tire is mounted on the vehicle, the circumferential groove includes an outer crown circumferential groove adjacent to the second tread end side of the middle land portion, The outer crown circumferential groove includes a plurality of width-changing portions in the tire circumferential direction, the width of which is gradually decreased toward one side in the tire circumferential direction. tire.

2. A tire having a tread portion, the tread portion includes a first tread edge and a second tread edge, a plurality of circumferential grooves extending continuously in a tire circumferential direction between the first tread edge and the second tread edge, and a middle land portion disposed on the first tread edge side relative to a tire equator and divided by the circumferential grooves, The middle land portion includes a plurality of middle blocks divided into a plurality of middle lateral grooves crossing the middle land portion, The middle lateral groove includes a first groove portion extending in the tire axial direction at the first tread end side and a second groove portion extending in the tire axial direction at the second tread end side, the second groove portion is offset from the first groove portion to one side in the tire circumferential direction, so that the middle lateral groove includes a longitudinal edge extending in the tire circumferential direction between an edge of the first groove portion and an edge of the second groove portion, the middle block includes a first circumferential edge on the first tread end side and a second circumferential edge on the second tread end side, The middle block is provided with an interrupted groove extending from the first circumferential edge and having an interrupted end within the middle block, The interrupted end of the interrupted groove is located closer to the first circumferential edge than the longitudinal edge, The length of the vertical edge in the tire circumferential direction is 40% to 60% of the groove width of the first groove portion, The maximum depth of the middle lateral groove is 40% to 60% of the maximum depth of the circumferential groove. tire.

3. A tire having a tread portion, the tread portion includes a first tread edge and a second tread edge, a plurality of circumferential grooves extending continuously in a tire circumferential direction between the first tread edge and the second tread edge, and a middle land portion disposed on the first tread edge side relative to a tire equator and divided by the circumferential grooves, The middle land portion includes a plurality of middle blocks divided into a plurality of middle lateral grooves crossing the middle land portion, The middle lateral groove includes a first groove portion extending in the tire axial direction at the first tread end side and a second groove portion extending in the tire axial direction at the second tread end side, the second groove portion is offset from the first groove portion to one side in the tire circumferential direction, so that the middle lateral groove includes a longitudinal edge extending in the tire circumferential direction between an edge of the first groove portion and an edge of the second groove portion, the middle block includes a first circumferential edge on the first tread end side and a second circumferential edge on the second tread end side, The middle block is provided with an interrupted groove extending from the first circumferential edge and having an interrupted end within the middle block, The interrupted end of the interrupted groove is located closer to the first circumferential edge than the longitudinal edge, a maximum depth of the middle lateral groove is 40% to 60% of a maximum depth of the circumferential groove, The axial length of the interrupted groove is 40% to 60% of the axial length of the first groove portion. tire.

4. A tire having a tread portion, the tread portion includes a first tread edge and a second tread edge, a plurality of circumferential grooves extending continuously in a tire circumferential direction between the first tread edge and the second tread edge, and a middle land portion disposed on the first tread edge side relative to a tire equator and divided by the circumferential grooves, The middle land portion includes a plurality of middle blocks divided into a plurality of middle lateral grooves crossing the middle land portion, The middle lateral groove includes a first groove portion extending in the tire axial direction at the first tread end side and a second groove portion extending in the tire axial direction at the second tread end side, the second groove portion is offset from the first groove portion to one side in the tire circumferential direction, so that the middle lateral groove includes a longitudinal edge extending in the tire circumferential direction between an edge of the first groove portion and an edge of the second groove portion, the middle block includes a first circumferential edge on the first tread end side and a second circumferential edge on the second tread end side, The middle block is provided with an interrupted groove extending from the first circumferential edge and having an interrupted end within the middle block, The interrupted end of the interrupted groove is located closer to the first circumferential edge than the longitudinal edge, a maximum depth of the middle lateral groove is 40% to 60% of a maximum depth of the circumferential groove, The longitudinal edge extends at an angle of 5° or less with respect to the circumferential direction of the tire. tire.

5. The middle block is provided with a sipe pair in which two sipes are adjacent to each other in the tire axial direction, 5. The tire according to claim 1, wherein the sipe pair includes a first middle sipe extending from the first circumferential edge and having an interrupted end within the middle block, and a second middle sipe extending from the second circumferential edge and having an interrupted end within the middle block.

6. A tire having a tread portion, the tread portion includes a first tread edge and a second tread edge, a plurality of circumferential grooves extending continuously in a tire circumferential direction between the first tread edge and the second tread edge, and a middle land portion disposed on the first tread edge side relative to a tire equator and divided by the circumferential grooves, The middle land portion includes a plurality of middle blocks divided into a plurality of middle lateral grooves crossing the middle land portion, The middle lateral groove includes a first groove portion extending in the tire axial direction at the first tread end side and a second groove portion extending in the tire axial direction at the second tread end side, the second groove portion is offset from the first groove portion to one side in the tire circumferential direction, so that the middle lateral groove includes a longitudinal edge extending in the tire circumferential direction between an edge of the first groove portion and an edge of the second groove portion, the middle block includes a first circumferential edge on the first tread end side and a second circumferential edge on the second tread end side, The middle block is provided with an interrupted groove extending from the first circumferential edge and having an interrupted end within the middle block, The interrupted end of the interrupted groove is located closer to the first circumferential edge than the longitudinal edge, The middle block is provided with a sipe pair in which two sipes are adjacent to each other in the tire axial direction, The sipe pair includes a first middle sipe extending from the first circumferential edge and having an interrupted end within the middle block, and a second middle sipe extending from the second circumferential edge and having an interrupted end within the middle block, The distance in the tire axial direction from the end of the first middle sipe to the end of the second middle sipe is 3% to 7% of the maximum width in the tire axial direction of the middle block. tire.

7. A tire having a tread portion, the tread portion includes a first tread edge and a second tread edge, a plurality of circumferential grooves extending continuously in a tire circumferential direction between the first tread edge and the second tread edge, and a middle land portion disposed on the first tread edge side relative to a tire equator and divided by the circumferential grooves, The middle land portion includes a plurality of middle blocks divided into a plurality of middle lateral grooves crossing the middle land portion, The middle lateral groove includes a first groove portion extending in the tire axial direction at the first tread end side and a second groove portion extending in the tire axial direction at the second tread end side, the second groove portion is offset from the first groove portion to one side in the tire circumferential direction, so that the middle lateral groove includes a longitudinal edge extending in the tire circumferential direction between an edge of the first groove portion and an edge of the second groove portion, the middle block includes a first circumferential edge on the first tread end side and a second circumferential edge on the second tread end side, The middle block is provided with an interrupted groove extending from the first circumferential edge and having an interrupted end within the middle block, The interrupted end of the interrupted groove is located closer to the first circumferential edge than the longitudinal edge, The length of the vertical edge in the tire circumferential direction is 40% to 60% of the groove width of the first groove portion, The middle block is provided with a sipe pair in which two sipes are adjacent to each other in the tire axial direction, The sipe pair includes a first middle sipe extending from the first circumferential edge and having an interrupted end within the middle block, and a second middle sipe extending from the second circumferential edge and having an interrupted end within the middle block, The middle block is provided with a third middle sipe extending from the second circumferential edge and having an interrupted end within the middle block on the first circumferential edge side relative to the longitudinal edge. tire.

8. A tire having a tread portion, the tread portion includes a first tread edge and a second tread edge, a plurality of circumferential grooves extending continuously in a tire circumferential direction between the first tread edge and the second tread edge, and a middle land portion disposed on the first tread edge side relative to a tire equator and divided by the circumferential grooves, The middle land portion includes a plurality of middle blocks divided into a plurality of middle lateral grooves crossing the middle land portion, The middle lateral groove includes a first groove portion extending in the tire axial direction at the first tread end side and a second groove portion extending in the tire axial direction at the second tread end side, the second groove portion is offset from the first groove portion to one side in the tire circumferential direction, so that the middle lateral groove includes a longitudinal edge extending in the tire circumferential direction between an edge of the first groove portion and an edge of the second groove portion, the middle block includes a first circumferential edge on the first tread end side and a second circumferential edge on the second tread end side, The middle block is provided with an interrupted groove extending from the first circumferential edge and having an interrupted end within the middle block, The interrupted end of the interrupted groove is located closer to the first circumferential edge than the longitudinal edge, The length of the interrupted groove in the tire axial direction is 40% to 60% of the length of the first groove portion in the tire axial direction, The middle block is provided with a sipe pair in which two sipes are adjacent to each other in the tire axial direction, The sipe pair includes a first middle sipe extending from the first circumferential edge and having an interrupted end within the middle block, and a second middle sipe extending from the second circumferential edge and having an interrupted end within the middle block, The middle block is provided with a third middle sipe extending from the second circumferential edge and having an interrupted end within the middle block on the first circumferential edge side relative to the longitudinal edge. tire.

9. A tire having a tread portion, the tread portion includes a first tread edge and a second tread edge, a plurality of circumferential grooves extending continuously in a tire circumferential direction between the first tread edge and the second tread edge, and a middle land portion disposed on the first tread edge side relative to a tire equator and divided by the circumferential grooves, The middle land portion includes a plurality of middle blocks divided into a plurality of middle lateral grooves crossing the middle land portion, The middle lateral groove includes a first groove portion extending in the tire axial direction at the first tread end side and a second groove portion extending in the tire axial direction at the second tread end side, the second groove portion is offset from the first groove portion to one side in the tire circumferential direction, so that the middle lateral groove includes a longitudinal edge extending in the tire circumferential direction between an edge of the first groove portion and an edge of the second groove portion, the middle block includes a first circumferential edge on the first tread end side and a second circumferential edge on the second tread end side, The middle block is provided with an interrupted groove extending from the first circumferential edge and having an interrupted end within the middle block, The interrupted end of the interrupted groove is located closer to the first circumferential edge than the longitudinal edge, The middle block is provided with a sipe pair in which two sipes are adjacent to each other in the tire axial direction, The sipe pair includes a first middle sipe extending from the first circumferential edge and having an interrupted end within the middle block, and a second middle sipe extending from the second circumferential edge and having an interrupted end within the middle block, The middle block is provided with a third middle sipe that extends from the second circumferential edge and has an interrupted end within the middle block on the first circumferential edge side relative to the longitudinal edge, The longitudinal edge extends at an angle of 5° or less with respect to the circumferential direction of the tire. tire.

10. A tire as described in any one of claims 6 to 9, wherein the interrupted end of the first middle sipe is located closer to the first circumferential edge than the vertical edge.

11. The tread portion has a specified orientation for mounting on a vehicle, The first tread edge is on the outer side of the vehicle when the tire is mounted on the vehicle, the tread portion includes an outer shoulder land portion adjacent to the first tread end side of the middle land portion with the circumferential groove interposed therebetween, The outer shoulder land portion is provided with a plurality of outer shoulder lateral grooves crossing the outer shoulder land portion, 11. The tire according to claim 1, wherein, in a plan view of the tread, an axially inner end portion of the outer shoulder lateral groove overlaps with a projected area obtained by extending an axially outer end portion of the interrupted groove parallel to the tire axial direction.

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