JP7377091B2 - pneumatic tires - Google Patents

Description

The present invention relates to a pneumatic tire.

Patent Document 1 discloses a pneumatic tire in which widthwise sipes extending in the widthwise direction of the tire are formed in blocks partitioned into a tread portion. Patent Document 1 discloses a case in which the widthwise sipe is configured as a straight sipe (FIG. 1) and a case in which it is configured as a waveform sipe having an amplitude in the longitudinal direction (FIG. 2).

International Publication No. 2012/133334

When the widthwise sipes are configured as straight sipes, the edge effect of the straight sipes tends to improve traction performance and braking performance. However, a pair of portions that are adjacent to each other in the tire circumferential direction with a straight sipe in between do not support each other against forces that act in the tire width direction, for example, when turning. For this reason, the straight sipes tend to cause increased deformation of the block in the tire width direction, which tends to deteriorate steering stability.

On the other hand, when the width direction sipes are configured as wave-shaped sipes, a pair of adjacent parts in the tire circumferential direction with the wave-shaped sipes in between engage and support each other against forces acting in the width direction of the tire. Increase in deformation in the width direction is suppressed. However, in the width direction sipe, the edge component extending in the tire width direction is reduced, so the edge effect is reduced.

An object of the present invention is to suppress deterioration of steering stability while suitably exhibiting an edge effect in a pneumatic tire in which widthwise sipes are formed in blocks partitioned into a tread portion.

The present invention
A pneumatic tire in which widthwise sipes extending in the widthwise direction of the tire are formed in a land portion divided into a tread portion,
The width direction sipe is
one or more sipe line portions extending linearly or curved;
one or more sipe waveform portions having an amplitude in the tire circumferential direction;
The sipe line part has a shallow sipe part in the middle part in the longitudinal direction, the groove depth being shallower than the remaining part ,
A pneumatic tire is provided in which, in the longitudinal direction of the widthwise sipe, a ratio of the length of the shallow sipe portion to the length of the sipe line portion is 0.2 or more and 0.6 or less.

According to the present invention, since the widthwise sipe has the sipe line part and the sipe waveform part, the edge effect by the sipe line part is suitably exerted, and the sipe waveform part allows the land area to be It is easy to resist the force generated in the width direction of the tire.

In addition, since the sipe line part has a shallow sipe part, even if a force is applied in the tire width direction, the parts connected in the tire circumferential direction via the shallow sipe part support each other, and deformation to is suppressed. In addition, the shallow sipe portion tends to prevent the sipe line portion from being blocked even when the vehicle touches the ground. As a result, deformation in the tire width direction is suppressed by the shallow sipe portion while exerting the edge effect at the sipe line portion. As a result, while the edge effect is exhibited, deterioration in steering stability is suppressed.
Moreover, in the longitudinal direction of the widthwise sipe, the ratio of the length of the shallow sipe to the length of the sipe line is 0.2 or more and 0.6 or less, so the edge effect due to the sipe line and the shallow sipe The effect of suppressing the deterioration of steering stability due to this can be suitably achieved. If the ratio is less than 0.2, the suppression of deterioration in steering stability due to the shallow sipe portion is likely to be insufficient. When the ratio exceeds 0.6, the edge effect due to the sipe line portion tends to be insufficient.

Preferably, the shallow sipe portion is provided in a portion where the sipe line portion has a predetermined length or more.

According to this configuration, a shallow sipe portion is not unnecessarily provided even when the sipe line portion is short, and the edge effect due to the sipe line portion can be obtained more favorably.

Further, preferably, a plurality of the widthwise sipes are formed at intervals in the tire circumferential direction,
In the pair of width direction sipes adjacent to each other in the tire circumferential direction, the respective shallow sipe portions are located at different positions in the tire width direction.

According to this configuration, shallow sipe portions having relatively high rigidity are not lined up in the tire circumferential direction in a pair of width direction sipes that are adjacent to each other in the tire circumferential direction. As a result, there are no parts where the stiffness is locally increased in the width direction of the tire, so local fluctuations in stiffness are easily suppressed and wear resistance is improved.

Preferably, the groove thickness of the sipe line portion is larger than the groove thickness of the sipe corrugated portion.

According to this configuration, the sipe line portion becomes less likely to be occluded when the vehicle touches the ground, so that the edge effect of the sipe line portion is more suitably exhibited.

Preferably, the widthwise sipes are formed on the outermost land portion located at the outermost side in the widthwise direction of the tire.

According to this configuration, the above-mentioned effects of the present invention are suitably exhibited in the outer land portion where force in the tire width direction is likely to act when turning or the like.

According to the present invention, in a pneumatic tire in which widthwise sipes are formed in blocks partitioned into a tread portion, deterioration in steering stability is suppressed while suitably exhibiting edge components.

FIG. 1 is a developed view of a tread portion of a pneumatic tire according to an embodiment of the present invention. FIG. 2 is an enlarged view of the first side block in FIG. 1; A sectional view taken along the line III-III in FIG. 2. A sectional view taken along the line IV-IV in FIG. 2. FIG. 4 is a cross-sectional view similar to FIG. 3 according to a modification. FIG. 4 is a sectional view similar to FIG. 3 according to a further modification.

Embodiments of the present invention will be described below with reference to the accompanying drawings. Note that the following description is essentially just an example, and is not intended to limit the present invention, its applications, or its uses. Further, the drawings are schematic, and the ratio of each dimension is different from the actual one.

FIG. 1 is a developed view showing a tread portion 1 of a pneumatic tire according to this embodiment. Although not shown, this pneumatic tire has a structure in which a carcass is stretched between a pair of bead cores, reinforced by a belt wrapped around the outer circumferential side of the middle part of the carcass, and a tread portion 1 is provided on the outer diameter side of the tire. .

In the following description, in FIG. 1, the left-right direction will be referred to as the tire width direction TW, the right side will be referred to as the TW1 side, and the left side will be referred to as the TW2 side. Further, in FIG. 1, the vertical direction is referred to as the tire circumferential direction TC, the upper side is referred to as the TC1 side, and the lower side is referred to as the TC2 side. Note that the pneumatic tire according to the present embodiment has a designated rotation direction, with the tire circumferential direction TC2 side being the stepping side and the tire circumferential direction TC1 side being the kicking side.

Further, FIG. 1 also shows the grounding shape GS. The contour shape of the ground contact shape GS includes a pair of width direction ground contact ends GT extending in the tire circumferential direction TC on both sides of the tire width direction TW, and a pair of circumferential direction ground contact ends GL extending in the tire width direction TW on both sides of the tire circumferential direction TC. It has The circumferential ground contact end GL extends in an arc shape with a ground contact shape GS convex in the tire circumferential direction TC at the tire equator line Ce.

Note that the ground contact shape GS in this specification refers to the maximum load at the normal internal pressure when a new (that is, unworn) pneumatic tire is assembled on a regular rim and filled with air at the regular internal pressure. This means a ground contact shape that makes contact with the flat road surface of the top surface of the tread portion 1 when a load of 90% of the capacity is applied.

A "regular rim" is a rim specified for each tire by the standard in the standard system that includes the standard on which the tire is based, for example, "standard rim" for JATMA, "Design Rim" for TRA, and rim for ETRTO. If so, it would be "Measuring Rim".

"Regular internal pressure" is the air pressure specified for each tire by each standard in the standard system including the standard on which the tire is based, and for JATMA it is the "maximum air pressure", and for TRA it is the air pressure specified in the table "TIRE LOAD LIMITS". The maximum value described in "AT VARIOUS COLD INFLATION PRESSURES" is "INFLATION PRESSURE" for ETRTO.

"Regular load" is the load specified for each tire by each standard in the standard system including the standard on which the tire is based, and in the case of JATMA it is the "maximum load capacity", and in the case of TRA it is the load specified in the table "TIRE LOAD". The maximum value listed in "LIMITS AT VARIOUS COLD INFLATION PRESSURES" is "LOAD CAPACITY" for ETRTO.

A tread pattern is formed in the tread portion 1 by a plurality of grooves. The groove portion includes a first inclined groove 11 extending obliquely from the vicinity of the tire equator line Ce toward the tire width direction TW1 side, and a second inclined groove extending obliquely from the vicinity of the tire equator line Ce toward the tire width direction TW2 side. 12 is included.

The base end of the first inclined groove 11 is located on the tire width direction TW2 side across the tire equator line Ce, and communicates with the middle of the second inclined groove 12. The first inclined groove 11 extends from the base end toward the tire circumferential direction TC1 side toward the tire width direction TW1 side while gradually increasing the width dimension. The first inclined groove 11 curves convexly toward the tire width direction TW1 side toward the tire circumferential direction TC1 side, and terminates beyond the widthwise ground contact end GT located on the tire width direction TW1 side. The first inclined groove 11 has a large inclination angle with respect to a straight line extending in the tire width direction TW on the tire equator line Ce side, and this inclination angle gradually becomes smaller toward the tire width direction TW1 side. The side end portion extends substantially along the tire width direction TW.

A plurality of first inclined grooves 11 are provided at predetermined intervals in the tire circumferential direction TC. The first inclined grooves 11 adjacent to each other in the tire circumferential direction TC are connected by a first circumferential groove 21 extending in the tire circumferential direction TC. The first circumferential groove 21 is inclined toward the tire circumferential direction TC2 side and toward the tire width direction TW1 side. The first circumferential groove 21 has a shallower groove depth than the first inclined groove 11 .

A third inclined groove 13 extends from an intermediate portion of the first circumferential groove 21 . The third inclined groove 13 divides the land portion formed between the first inclined grooves 11 adjacent in the tire circumferential direction TC into two. The end position of the third inclined groove 13 is closer to the tire equator line Ce than the end position of the first inclined groove 11.

The first inclined groove 11 and the third inclined groove 13 are connected by a second circumferential groove 22 extending in the tire circumferential direction. The second circumferential groove 22 is inclined toward the tire circumferential direction TC2 side and toward the tire width direction TW1 side. The second circumferential groove 22 is located closer to the tire width direction TW1 than the first circumferential groove 21, and has a shallower groove depth than the first and third inclined grooves 11 and 13. The second circumferential grooves 22 adjacent to each other in the tire circumferential direction TC are shifted in position in the tire width direction TW. That is, the second circumferential grooves 22 are alternately provided so as to be shifted toward the tire width direction TW1 side and the tire equator line Ce side toward the tire circumferential direction TC.

The first center block 2 is defined by two first inclined grooves 11, second inclined grooves 12, and first circumferential grooves 21 that are adjacent to each other in the tire circumferential direction TC. The first center block 2 has a rhombic shape that is longer in the tire circumferential direction TC than in the tire width direction TW. The first center blocks 2 are arranged in the tire circumferential direction TC to form a first center block row.

The first mediate block 3 is defined by the first inclined groove 11, the third inclined groove 13, the first circumferential groove 21, and the second circumferential groove 22. The first mediate block 3 has a laterally elongated shape that extends in the tire width direction TW compared to the tire circumferential direction TC. The first mediate blocks 3 are arranged in the tire circumferential direction TC to form a first mediate block row. In the first mediate block row, the shapes of the first mediate blocks 3 adjacent to each other in the tire circumferential direction TC are slightly different.

That is, since the first circumferential groove 21 is inclined in the tire width direction TW1 toward the tire circumferential direction TC2 side, the pair of first mediate blocks 3 partitioned by the first circumferential groove 21 are The positions of the inner end portions in the width direction TW are different. Furthermore, the groove width of the first circumferential groove 21 is different between the upper and lower portions with the third inclined groove 13 in between. Further, the positions of the second circumferential grooves 22 adjacent to each other in the tire circumferential direction TC are shifted from each other in the tire width direction TW.

The first shoulder block 4 is defined by the first inclined groove 11, the third inclined groove 13, and the second circumferential groove 22. The first shoulder block 4 has a laterally elongated shape that extends further in the tire width direction TW than the tire circumferential direction TC compared to the first mediate block 3. The first shoulder block 4 extends in the tire width direction TW beyond the width direction ground contact end GT. The first shoulder blocks 4 are arranged in the tire circumferential direction TC to form a first shoulder block row. As described above, since the second circumferential grooves 22 are alternately shifted in the tire width direction TW toward the tire circumferential direction TC, the positions of the end portions of the respective first shoulder blocks 4 are also different.

One block set is formed by one first center block 2, two first mediate blocks 3, and two first shoulder blocks 4 between a pair of first inclined grooves 11 adjacent to each other in the tire circumferential direction. The body is made up of

The base end of the second inclined groove 12 is located on the tire width direction TW1 side across the tire equator line Ce, and communicates with the middle of the first inclined groove 11. The second inclined groove 12 extends from the base end toward the tire circumferential direction TC1 side toward the tire width direction TW2 side while gradually increasing the width dimension. The second inclined groove 12 curves in a convex manner toward the tire width direction TW2 side toward the tire circumferential direction TC1 side, and terminates beyond the widthwise ground contact end GT located on the tire width direction TW2 side. The second inclined groove 12 has a large inclination angle with respect to a straight line extending in the tire width direction TW on the tire equator line Ce side, and this inclination angle gradually becomes smaller as it goes toward the tire width direction TW2 side. The side end portion extends substantially along the tire width direction TW.

A plurality of second inclined grooves 12 are provided at predetermined intervals (same as the first inclined grooves 11) in the tire circumferential direction TC. The second inclined grooves 12 adjacent to each other in the tire circumferential direction TC are connected by a third circumferential groove 23 extending in the tire circumferential direction TC. A fourth inclined groove 14 extends from an intermediate portion of the third circumferential groove 23 . The fourth inclined groove 14 divides the land portion formed between the second inclined grooves 12 adjacent to each other in the tire circumferential direction TC into two. The second inclined groove 12 and the fourth inclined groove 14 are connected by a fourth circumferential groove 24 extending in the tire circumferential direction TC. The third and fourth circumferential grooves 23 and 24 are inclined toward the tire circumferential direction TC2 side and toward the tire width direction TW2 side.

The second center block 5 is defined by two second inclined grooves 12, a first inclined groove 11, and a third circumferential groove 23 that are adjacent to each other in the tire circumferential direction TC. The second center blocks 5 are arranged in the tire circumferential direction TC to form a second center block row.

The second mediate block 6 is defined by the second inclined groove 12, the fourth inclined groove 14, the third circumferential groove 23, and the fourth circumferential groove 24. The second mediate blocks 6 are arranged in the tire circumferential direction TC to form a second mediate block row.

The second shoulder block 7 is defined by the second inclined groove 12, the fourth inclined groove 14, and the fourth circumferential groove 24. The second shoulder blocks 7 are arranged in the tire circumferential direction TC to form a second shoulder block row.

One block set is formed by one second center block 5, two second mediate blocks 6, and two second shoulder blocks 7 between a pair of second inclined grooves 12 adjacent to each other in the tire circumferential direction. The body is made up of

The base end of the first inclined groove 11 communicates with the middle of the second inclined groove 12 at a position on the left beyond the tire equator line Ce, and extends diagonally upward to the right in a curved state. At a position next to the tire circumferential direction TC, the base end of the second inclined groove 12 communicates with the middle of the first inclined groove 11 at a position on the right beyond the tire equator line Ce, and extends diagonally upward to the left. Extends in a curved manner. That is, the first slanted groove 11 and the second slanted groove 12 form a V-shape, and their communication positions are alternately located on either side of the tire equator line Ce in the tire circumferential direction TC.

In the tread portion 1 having the above configuration, each block has sipes formed by a plurality of cuts. The term sipe used here refers to a groove with a thickness (dimension in the direction perpendicular to the longitudinal direction of the groove) that closes the groove when the groove touches the ground.For example, the groove thickness is set to 1.5 mm or less. In this embodiment, it is set to 0.5 mm.

A plurality of first center sipes 40 and a plurality of first mediate sipes 30 are formed in the first center block 2 and the first mediate block 3, respectively. A plurality of first center sipes 40 and first mediate sipes 30 are formed in a diagonal direction so as to be substantially perpendicular to a diagonal line along the tire circumferential direction TC of the first center block 2 and first mediate block 3. has been done. This makes it easy to increase the number of first center sipes 40 and first mediate sipes 30 while forming them so as to extend in a direction closer to the tire width direction TW rather than the tire circumferential direction TC. .

In FIG. 2, the first shoulder block 4 is shown enlarged. As shown in FIG. 2, the first shoulder block 4 is formed with a first shoulder sipe 50 extending in the tire width direction TW. The first shoulder sipes 50 are formed substantially parallel to the first inclined groove 11 and the third inclined groove 13, and are formed in plural at intervals in the tire circumferential direction. The first shoulder sipe 50 alternately includes a plurality of sipe line portions 51 extending linearly or curved along the longitudinal direction and a plurality of sipe waveform portions 52 having an amplitude in the tire circumferential direction. Note that the first shoulder sipe 50 may be configured by one sipe line portion 51 and one sipe waveform portion 52.

FIG. 3 is a cross-sectional view taken along the first sipe 50A located closest to the tire circumferential direction TC1 among the plurality of first shoulder sipes 50. Referring also to FIG. 2, the first sipe 50A has a shallow sipe portion 53 with a raised groove bottom in the middle of the sipe line portion 51 in the longitudinal direction. In other words, in the sipe line portion 51, the shallow sipe portion 53 has a shallower groove depth than the remaining portion.

Further, the shallow sipe portion 53 is provided only for the sipe line portion 51 having a length L1 of 4 mm or more in the longitudinal direction. The shallow sipe ratio R, which is the ratio of the length L2 of the shallow sipe portion 53 to the length L1 of the sipe line portion 51, is set to 0.2 or more and 0.6 or less.

In this embodiment, the shallow sipe portion 53A formed in the first sipe 50A is formed to be wide in the tire width direction TW2 side toward the groove bottom. Furthermore, the shallow sipe portion 53A is provided closer to the tire width direction TW2 than the longitudinal center of the sipe line portion 51.

The end of the first shoulder block 4 on the tire width direction TW2 side extends toward the tire width direction TW1 side toward the tire circumferential direction TC2 according to the extending direction of the second circumferential groove 22 that partitions the end. It is sloping. For this reason, the second sipe 50B adjacent to the first sipe 50A in the tire circumferential direction TC2 side extends the first sipe 50A along the second circumferential groove 22 on the tire circumferential direction TC2 side and on the tire width direction TW1 side. It is formed in a staggered manner.

Therefore, the shallow sipe portion 53B formed in the second sipe 50B is shifted in position in the tire width direction TW1 side with respect to the shallow sipe portion 53A of the first sipe 50A. Further, with reference also to FIG. 4, which is a cross-sectional view taken along the second sipe 50B of the first shoulder block 4 on line IV-IV in FIG. 2, the shallow sipe portion 53B is The sipe line portion 51A is provided closer to the tire width direction TW1 than the center portion in the longitudinal direction.

Therefore, as shown in FIG. 2, in a pair of first and second sipes 50A, 50B adjacent to each other in the tire circumferential direction TC, shallow sipe portions 53A, 53B formed in sipe line portions 51A, 51B, respectively, The positions are different in the width direction TW. In other words, when viewed from the tire circumferential direction TC, the shallow sipe portions 53A and 53B are configured so as not to overlap with each other.

Although not shown, in the third sipe 50C adjacent to the second sipe 50B in the tire circumferential direction TC2, the shallower sipe portion 53C is wider in the tire width direction than the longitudinal center of the sipe line portion 51C. It is provided on the TW2 side and is formed to be wide in the tire width direction TW2 side toward the groove bottom.

Therefore, in the first shoulder sipes 50 adjacent to each other in the tire circumferential direction TC, the shallow sipe portions 53 formed in the respective sipe line portions 51 are connected to the tire width direction TW1 side and the tire so as not to overlap when viewed from the tire circumferential direction. They are provided in alternating positions on the width direction TW2 side.

In this embodiment, the top surface 53a of the shallow sipe portion 53 located on the outside in the tire radial direction is located at the same height as the surface of the first shoulder block 4 located on the outside in the tire radial direction. Note that, as shown in FIG. 5, the top surface 53a of the shallow sipe portion 53 may be formed to be located inside the surface of the first shoulder block 4 in the tire radial direction. In this case, the distance D between the top surface 53a of the shallow sipe portion 53 and the surface of the first shoulder block 4 is set to 4 mm or less. Further, as shown in FIG. 6, the shallow sipe portion 53 may be formed in a rectangular shape having a constant width in the tire radial direction.

As shown in FIG. 1, the second center block 5, second mediate block 6, and second shoulder block 7 also have a second center sipe 60, a second mediate sipe 70, and a second shoulder sipe. 80 are formed respectively. The configuration of the second center sipe 60, second mediate sipe 70, and second shoulder sipe 80 is such that the first center sipe 40, first mediate sipe 30, and first shoulder sipe 50 are aligned with respect to the tire equator line Ce. This is a structure in which the structure is substantially line symmetrical and shifted by a predetermined pitch in the circumferential direction of the tire, and a detailed description thereof will be omitted.

According to the pneumatic tire described above, the following effects can be obtained. Note that although the following effects will be described with respect to the first shoulder block 4, they can be similarly obtained with the second shoulder block 7.

(1) Since the first shoulder sipe 50 has the sipe line part 51 and the sipe waveform part 52, the edge effect of the sipe line part 51 can be suitably exhibited, and the sipe waveform part 52 can be used, for example, when turning. In this case, the first shoulder sipe 50 can easily resist the force generated in the tire width direction TW.

Further, since the sipe line portion 51 has the shallow sipe portion 53, even if a force acts in the tire width direction TW, the portions connected in the tire circumferential direction TC via the shallow sipe portion 53 will not support each other. As a result, deformation in the tire width direction TW is suppressed. Further, the shallow sipe portion 53 tends to prevent the sipe line portion 51 from being blocked even when the vehicle touches the ground. As a result, deformation in the tire width direction TW is suppressed by the shallow sipe portion 53 while exerting the edge effect in the sipe line portion 51. As a result, while the edge effect is exhibited, deterioration in steering stability is suppressed.

(2) Since the shallow sipe portion 53 is provided when the length L1 of the sipe line portion 51 is 4 mm or more, the shallow sipe portion 53 is unnecessarily formed even when the sipe line portion 51 is short. The edge effect by the sipe line portion 51 can be obtained more suitably without being provided.

(3) In a pair of first shoulder sipes 50 adjacent to each other in the tire circumferential direction TC, shallow sipe portions 53 having relatively high rigidity are not lined up in the tire circumferential direction TC. As a result, a portion where the stiffness locally becomes high does not occur in the tire width direction TW, so that local fluctuations in stiffness can be easily suppressed and wear resistance is improved.

(4) Since the shallow sipe ratio R is set to 0.2 or more and 0.6 or less, the edge effect due to the sipe line portion 51 and the effect of suppressing deterioration of steering stability due to the shallow sipe portion 53 are preferably compatible. be done. If the ratio is less than 0.2, the suppression of deterioration in steering stability due to the shallow sipe portion is likely to be insufficient. When the ratio exceeds 0.6, the edge effect due to the sipe line portion tends to be insufficient.

(5) Since the shallow sipe portion 53 is formed in the first shoulder block 4 on which force tends to act in the width direction of the tire when turning, etc., it is easy to improve maneuverability.

In the above embodiment, the first shoulder sipe 50 has been described using an example in which the groove thickness is constant at 0.5 mm, but the groove thickness is not limited to this. That is, in the first shoulder sipe 50, the groove thickness may be made different between the sipe line portion 51 and the sipe waveform portion 52. In this case, the groove thickness in the sipe line portion 51 may be increased compared to the sipe waveform portion 52. For example, the groove thickness of the sipe waveform portion 52 may be 0.5 mm, and the groove thickness of the sipe line portion 51 may be 0.8 mm. As a result, the sipe line portion 51 becomes less likely to be blocked when touching the ground, so that the edge effect of the sipe line portion 51 is more suitably exhibited.

In the above embodiment, the case where the shallow sipe portions 53 are formed in the first and second shoulder sipes 50 and 80 formed on the first and second shoulder blocks 4 and 7 has been described as an example, but the invention is not limited to this. . In the first center block 2, the first mediate block 3, the second center block 5, and the second mediate block 6, if there is a sipe line portion with a predetermined length or more, a shallow sipe line is attached to the sipe line portion. It is also possible to form a section.

Note that the present invention is not limited to the configuration described in the above embodiments, and various changes are possible.

1 Tread portion 2 First center block 3 First mediate block 3L Diagonal line 4 First shoulder block 5 Second center block 6 Second mediate block 7 Second shoulder block 11 to 14 First to fourth inclined grooves 21 to 24 First to fourth circumferential grooves 30 First mediate sipe 40 First center sipe 50 First shoulder sipe 51 Sipe line portion 52 Sipe waveform portion 53 Shallow sipe portion 60 Second center sipe 70 Second mediate sipe 80 Second shoulder sipe

Claims (5)

A pneumatic tire in which widthwise sipes extending in the widthwise direction of the tire are formed in a land portion divided into a tread portion,
The width direction sipe is
one or more sipe line portions extending linearly or curved;
one or more sipe waveform portions having an amplitude in the tire circumferential direction;
The sipe line part has a shallow sipe part in the middle part in the longitudinal direction, the groove depth being shallower than the remaining part ,
In the longitudinal direction of the widthwise sipe, the ratio of the length of the shallow sipe portion to the length of the sipe line portion is 0.2 or more and 0.6 or less. The shallow sipe portion is provided in a portion where the sipe line portion has a predetermined length or more,
The pneumatic tire according to claim 1. A plurality of the width direction sipes are formed at intervals in the tire circumferential direction,
In the pair of width direction sipes adjacent to each other in the tire circumferential direction, each shallow sipe portion is at a different position in the tire width direction.
The pneumatic tire according to claim 1 or 2. The groove thickness of the sipe line portion is larger than the groove thickness of the sipe corrugated portion.
The pneumatic tire according to any one of claims 1 to 3 . The width direction sipe is formed on an outer land portion located at the outermost side in the tire width direction.
The pneumatic tire according to any one of claims 1 to 4 .

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