JP7081177B2 - Tire mold - Google Patents

Description

The present invention relates to a tire mold. More specifically, it relates to a mold for manufacturing a tire having a sipe on the tread surface.

Tires for running on ice and snow roads have a large number of elongated grooves (hereinafter, also referred to as sipes) carved on the tread surface. The mold used in the manufacture of this tire comprises a mold body and a plurality of blades. The plurality of blades are arranged on the inner surface of the mold body. This blade forms a sipe on the tread surface. Japanese Patent Application Laid-Open No. 10-258429 discloses a mold provided with a blade.

Japanese Unexamined Patent Publication No. 10-258429

In some tire molds, a large number of segments are arranged in the circumferential direction to form the tread surface of the tire. In this mold, the blade extending to the circumferential end of the segment (the boundary position with the adjacent segment) is easily damaged near the circumferential end. By not forming a blade near the circumferential end of the segment, damage to this blade can be suppressed. Further, by lowering the height of the blade, damage to the blade can be suppressed.

However, in the case of a mold that does not form a blade near the circumferential end of the segment or a mold in which the height of the blade is lowered, the rigidity of the position corresponding to the boundary of the segment in the molded tire becomes higher than that around it. .. In the tread of this tire, there is a periodic difference in rigidity in the circumferential direction. This difference in periodic stiffness increases the radial force variation (RFV). This difference in periodic stiffness exacerbates the RFV of the tire.

An object of the present invention is to provide a mold capable of producing a tire with reduced RFV while suppressing blade breakage.

The tire mold according to the present invention vulcanizes a tire. The mold is arranged in the circumferential direction and includes a plurality of segments that form the tread surface of the tire. The segment comprises a main blade and a sub blade that form a sipe. The sub-blade has a low back portion whose height is lower than the height of the main blade, at least in a part thereof. The low back portion is arranged in the non-split position region of the segment.

Preferably, a plurality of the low back portions are arranged to form a blade low region where the height of the blade is low. The blade low region is formed in the split position region.

Preferably, a plurality of the low back portions are arranged to form a blade low region where the height of the blade is low. The blade low region is formed in the non-split position region.

In a state where a plurality of segments are arranged in the circumferential direction to form a ring, the distance between the blade low region and the blade low region adjacent to one in the circumferential direction is set to D1, and the distance from the blade low region adjacent to the other in the circumferential direction is defined as D1. Let the distance be D2. Preferably, at this time, the distance D1 and the distance D2 are different in each blade low region.

Preferably, the number of regions of the blade low region formed in each segment is 10 or less.

The height of the main blade is Hh, and the height of the blade at the low back portion is Hs. Preferably, at this time, the ratio of the height Hs to the height Hh is 0.7 or less.

In the tire according to the present invention, sipes are formed on the tread in a plurality of segments divided in the circumferential direction. In this tire, the sipe consists of a main sipe and a secondary sipe. The sub-sipe has a shallow depth portion shallower than the main sipe at least in a part thereof. The shallow and deep portion is formed in a non-parting line region corresponding to a non-split position region of the segment.

Preferably, the shallow and deep portions are gathered together to form a shallow sipe region in which the depth of the sipe is shallow. The shallow sipe region is formed in the parting line region.

Preferably, the shallow and deep portions are gathered together to form a shallow sipe region in which the depth of the sipe is shallow. The shallow sipe region is formed in the non-parting line region.

In this mold, the low back portion where the height of the blade is lowered is arranged in the non-split position region. Due to this low back portion, a portion having a rigidity different from that around the tire is formed in the non-split position region of the tire. In this mold, it is suppressed that a periodic rigidity difference occurs in the circumferential direction of the tire. With this tire, periodic vibration is suppressed. With this tire, the increase in RFV is suppressed. With this mold, damage to the blade can be suppressed and deterioration of the RFV of the tire can be suppressed.

FIG. 1 is a plan view showing a mold according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along the line II-II of FIG. FIG. 3 is a cross-sectional view showing the segment of FIG. FIG. 4 is an explanatory view showing a part of the blade of FIG. FIG. 5 is an explanatory view showing another part of the blade of FIG. FIG. 6 is a developed view showing a part of the inner surface of the segment of the mold of FIG.

Hereinafter, the present invention will be described in detail based on a preferred embodiment with reference to the drawings as appropriate.

FIG. 1 shows a mold 16 according to the present invention. The shape of the mold 16 is a ring shape. In FIG. 1, the direction of the double-headed arrow A is the circumferential direction of the mold 16, and the direction perpendicular to the paper surface is the axial direction of the mold 16.

FIG. 2 shows a cross-sectional view taken along the line segments II-II of FIG. In FIG. 2, the vertical direction is the axial direction of the mold 16, the left-right direction is the radial direction of the mold 16, and the direction perpendicular to the paper surface is the circumferential direction of the mold 16. FIG. 2 also shows the low cover R molded on the tire by the mold 16.

As shown in FIGS. 1 and 2, the mold 16 includes a plurality of segments 18, a pair of upper and lower side plates 20, and a pair of upper and lower bead rings 22.

As shown in FIG. 1, the planar shape of the segment 18 is substantially arcuate. The plurality of segments 18 are arranged in the circumferential direction. The plurality of arranged segments 18 are arranged in a ring shape. The circumferential end faces of adjacent segments 18 are in contact with each other. Reference numeral BL represents a split position, which is a boundary between segments 18 adjacent to each other in the circumferential direction. In this mold 16, nine segments 18 are arranged in the circumferential direction. In this mold 16, there are nine split positions BL. The split positions BL are located at equal intervals in the circumferential direction. The number of segments 18 is not limited to nine. The number of segments 18 may be greater than or less than nine.

Each side plate 20 has a ring shape. Each bead ring 22 has a ring shape.

In FIGS. 1 and 2, the mold 16 is in a closed state in which a plurality of segments 18, a pair of sipe plates 20, and a pair of bead rings 22 are in contact with each other. In this closed state, the inner surface 24 of the segment 18, the inner surface 26 of the side plate 20, and the inner surface 28 of the bead ring 22 constitute the cavity surface. This cavity surface comes into contact with the low cover R to form the outer surface of the tire.

As shown in FIG. 2, the inner surface 24 of each segment 18 abuts on the outer peripheral surface of the low cover R. The inner surface 26 of each side plate 20 comes into contact with the side portion of the low cover R. The inner surface 28 of each bead ring 22 abuts on the bead portion of the low cover R.

FIG. 3 shows a cross section of the segment 18. The segment 18 includes a main body 30 and a plurality of blades 32. The main body 30 includes a protrusion 34 and a bottom surface 36. The protrusion 34 is formed so as to stand up from the bottom surface 36 inward in the radial direction. Each blade 32 is located on the bottom surface 36. The blade 32 stands up from the bottom surface 36 inward in the radial direction.

FIG. 4 shows a part of the blade 32. The blade 32 includes a plurality of main blades 38 and a plurality of sub-blades 40. FIG. 4 shows an example of the main blade 38 and the sub blade 40 seen in the circumferential direction.

The double-headed arrow Hh in FIG. 4 represents the height of the main blade 38. The double-headed arrow Hs represents the height of the low back portion 42 of the auxiliary blade 40. The height Hh and the height Hs are measured as the height from the bottom surface 36 in the radial direction.

In FIG. 4, the main blade 38 is formed at a constant height Hh. The sub-blade 40 is entirely composed of a low back portion 42 lower than the main blade 38. In the present invention, the blade 32 having at least a part thereof having a low back portion 42 having a height of Hs is referred to as an auxiliary blade 40.

FIG. 5 shows a part of the auxiliary blade 40 (blade 32) at the split position BL together with a part of the main body 30. The auxiliary blade 40 has a zigzag shape. In the auxiliary blade 40, the plate-shaped portion and the bent portion are alternately and continuously formed in a zigzag shape.

The thickness of the blade 32 (main blade 38 and sub blade 40) is, for example, 0.3 mm to 1.3 mm. The material of a typical blade 32 is steel.

In FIG. 5, the auxiliary blade 40 extends to the split position BL. The low back portion 42 of the auxiliary blade 40 is located at this split position BL. In the segment 18, the auxiliary blade 40 extends to the circumferential end on the inner surface 24 thereof, and the low back portion 42 is located at the circumferential end of the segment 18.

The sub-blade 40 is composed of a main body portion 44 formed at a height Hh and a low back portion 42 formed at a height Hs between one end and the other end extending in a zigzag shape. As described above, the auxiliary blade 40 of the present invention may be provided with a low back portion 42 having a height of Hs as a part thereof.

FIG. 6 shows a part of the inner surface 24 of the segments 18 arranged in the circumferential direction. In FIG. 6, the left-right direction is the circumferential direction of the mold 16, the vertical direction is the axial direction of the mold 16, and the direction perpendicular to the paper surface is the radial direction of the mold 16. The alternate long and short dash line CL in FIG. 6 represents the equatorial plane of the mold 16 corresponding to the equatorial plane of the tire.

The segment 18 includes a plurality of protrusions 34 that rise from the bottom surface 36. These protrusions 34 extend substantially in the circumferential direction and make a full circle. The segment 18 includes a plurality of protrusions 48 that rise from the bottom surface 36. These protrusions 48 extend in the substantially axial direction. A plurality of recesses 50 are formed on the inner surface 24, separated by the protrusions 34 and 48. The bottom surface 36 forms the bottom surface of the recess 50.

As described above, a zigzag-shaped elongated blade 32 (main blade 38 and sub-blade 40) stands on each bottom surface 36. The blade 32 is provided over almost the entire surface of the bottom surface 36. As shown in the figure, the length of the blade 32 is not constant. There are blades 32 of various lengths.

In this mold 16, the blade 32 is composed of a main blade 38 and a sub blade 40. The main blade 38 is formed at a constant height Hh. The auxiliary blade 40 has a low back portion 42 having a height of Hs at least in a part thereof. In FIG. 1, for convenience of explanation, the low back portion 42 of the blades 32 is represented by a thick line.

In FIG. 6, the low back portions 42 of the plurality of auxiliary blades 40 are gathered to form the blade low region Ap and the blade low region Ad.

Each blade low region Ap is a region including the split position BL of the segment 18 in the circumferential direction. The blade low region Ap is formed so as to straddle the adjacent segments 18. The blade low region Ap extends axially from one end to the other on the inner surface 24 forming the tread surface.

The blade low region Ad is located between the split positions BL of the segment 18 in the circumferential direction. The blade low region Ad is located between the blade low region Ap in the circumferential direction. In this mold 16, the blade low region Ad extends axially from one end to the other on the inner surface 24 forming the tread surface.

The double-headed arrow Wp in FIG. 6 represents the circumferential width of the blade low region Ap. This width Wp is measured as the distance from one end of the blade low region Ap to the other end in the circumferential direction in the circumferential direction. This distance is measured in the circumferential direction along the bottom surface 36. The double-headed arrow Wd represents the circumferential width of the blade low region Ad. This width Wd is measured as the distance from one end of the blade low region Ad in the circumferential direction to the other end in the circumferential direction. This distance is measured in the circumferential direction along the bottom surface 36.

In this mold 16, the width Wd of the blade low region Ad is set to be the same as the width Wp of the blade low region Ap. The plurality of blade low region Aps are formed at a constant pitch in the circumferential direction. In FIG. 6, in the circumferential direction, the number of regions of the blade low region Ad between the blade low region Ap is 1, but is not limited to this. A plurality of blade low region Ads may be formed between the blade low region Aps. Further, the segment 18 in which the number of regions of the blade low region Ad between the blade low region Ap is 0 may be included.

The alternate long and short dash line DL represents a dummy line of segment 18. This dummy line DL represents the center line of the blade low region Ad. The dummy line DL extends axially along the bottom surface 36.

The double-headed arrow Dp in FIG. 6 represents the circumferential distance of the blade low region Aps adjacent to each other in the circumferential direction. The distance Dp is measured as the distance between the split positions BL along the bottom surface 36. The double-headed arrow D1 represents the circumferential distance between the blade low region Ad and the blade low region Ap adjacent to each other in the circumferential direction. The double-headed arrow D2 represents the circumferential distance between the blade low region Ad and the blade low region Ap adjacent to the other in the circumferential direction. This distance D1 is measured as the circumferential distance along the bottom surface 36 between the center line DL and the split position BL in one of the circumferential directions. This distance D2 is measured as the circumferential distance along the bottom surface 36 between the center line DL and the other split position BL in the circumferential direction.

In the mold 16 in which a plurality of blade low region Ad is formed between the blade low region Ap, the distances D1 and D2 are measured as the distance to the blade low region Ap or the blade low region Ad closest to the circumferential direction.

In this mold 16, the blade low region Ap is arranged in the split position region sandwiching the split position BL. Further, the blade low region Ad is arranged in the non-split position region other than the split position region. In the present invention, a region in which the central angle in the circumferential direction is in the range of plus or minus 5 ° with the split position BL as the center line is referred to as a split position region. The area other than the split position area of the inner surface 28 is referred to as a non-split position area. In this mold 16, a low back portion 42 is also formed in this non-split position region.

A method for manufacturing a tire using the mold 16 will be described. This tire manufacturing method includes a preforming step and a vulcanization step. In the preforming step, the rubber members forming each part of the tire are combined to form a low cover. In the vulcanization step, this low cover is charged into the mold 16. This low cover is pressurized and heated in the mold 16. This low cover is vulcanized to give the tire from the low cover.

In this tire, the outer surface of the tread is molded to follow the inner surface 24 of the ring-shaped segments 18. The outer surface of the sidewall is mainly formed following the inner surface 26 of the side plate 20. The outer surface of the bead is mainly formed following the inner surface 28 of the bead ring 22. The tread of this tire has a parting line corresponding to the split position. The tread surface of this tire is composed of a parting line region corresponding to a split position region and a non-parting line region corresponding to a non-split position region.

This tread surface is formed following the inner surface 24 of the segment 18. The protrusion 34 extending in the substantially circumferential direction forms a main groove extending in the substantially circumferential direction in the tread of the tire. The protrusion 48 extending in the substantially axial direction forms a lateral groove extending in the substantially axial direction in the tread of the tire. The recess 50 forms a block separated by a main groove and a lateral groove. The bottom surface 36 forms the outer surface of the block, which forms part of the tread surface.

The blade 32 (main blade 38 and sub blade 40) forms a sipe on the tread surface. This sipe is elongated on the tread surface and extends in a zigzag pattern. The sipe 32 is formed over substantially the entire tread surface of the block. Since this sipe is formed following the blade 32 of the mold 16, the length of the sipe is not constant. Sipes of various lengths are formed on the tread surface. Sipe contributes to the improvement of grip. This mold 16 is used for manufacturing tires used for traveling on icy and snowy roads. This mold 16 is a so-called studless tire mold.

In this tire, the sipe 14 is composed of a main sipe formed by the main blade 38 and a sub sipe formed by the sub blade 40. The main sipe has a constant depth. The sub-sipe has a shallow depth that is shallower than the depth of the main sipe, at least in part thereof. This shallow and deep portion is formed following the low back portion 42 of the auxiliary blade 40.

In this tire, the shallow depths of a plurality of sub-sipes are gathered to form a plurality of shallow sipe regions in which the depth of the sipe is shallow. This shallow sipe region is composed of a shallow parting sipe region formed following the low blade region Ap and a shallow dummy sipe region formed following the low blade region Ad.

Each parting sipe shallow area is located on the parting line corresponding to the split position. This parting sipe shallow region is a region including a parting line in the circumferential direction. This parting sipe shallow region extends in a strip shape from one end to the other in the axial direction. Since this parting sipe shallow region is formed following the blade low region Ap, it is formed with a circumferential width and an axial length substantially similar to the blade low region Ap. The distance between the shallow regions of the parting sipes adjacent to each other in the circumferential direction is formed by a substantially distance Dp, which is substantially the same as the blade low region Ap.

Each dummy sipe shallow region is located between the parting lines in the circumferential direction. This dummy sipe shallow region is located between the parting sipe shallow regions in the circumferential direction. In this tire, since the dummy sipe shallow region is formed following the blade low region Ad, it is formed with a circumferential width and an axial length substantially similar to the blade low region Ad. The distance between the dummy sipe shallow region and the parting sipe shallow region adjacent to each other in the circumferential direction is set to a substantially distance D1 and a substantially distance D2, which is substantially the same as the blade low region Ad.

In this mold 16, the auxiliary blade 40 is arranged in the vicinity of the split position BL. The low back portion 42 is arranged at the split position. As a result, when the segment 18 opens and closes in the radial direction, the blade 32 (low back portion 42) is prevented from being damaged in the vicinity of the split position.

On the other hand, in the tire formed by the mold 16, the sipes are shallow in the vicinity of the parting line. In the vicinity of this parting line, the rigidity of the tread tends to increase. In this mold 16, the low back portion 42 is also arranged in the non-split position region. In this tire 2, the periodic rigidity difference in the circumferential direction is relaxed. In this tire 2, periodic vibration caused by the split position BL is suppressed. The mold 16 can suppress an increase in RFV while suppressing damage to the blade 32.

In this mold 16, the blade low region Ap is formed at the split position BL. A sipe (shallow and deep part) is also formed in the parting line region corresponding to the split position region. This tire has a smaller difference in rigidity than a tire in which no sipes are formed in the parting line region. This can prevent the RFV of the tire from increasing. In addition, the formation of sipes in the parting line region contributes to the improvement of grip performance. From the viewpoint of RFV and grip performance, it is preferable that a shallow and deep portion is formed in the parting line region as in the mold 16.

Further, the blade low region Ad is different between the distance D1 and the distance D2. As a result, in the tire formed by the mold 16, the periodic rigidity difference is further reduced.

In the mold 16 in which the difference between the distance D1 and the distance D2 is large, the effect of alleviating the periodic rigidity difference of the tire can be easily obtained. From this point of view, the ratio (D1 / D2) is preferably 1.1 or more, more preferably 1.5 or more, and particularly preferably 2.0 or more. On the other hand, in the mold 16 in which this ratio (D1 / D2) is too large, the effect of alleviating the periodic rigidity difference of the tire is reduced. From this point of view, this ratio (D1 / D2) is preferably 8.0 or less, more preferably 6.0 or less, and particularly preferably 4.0 or less. Here, the mold 16 in which the distance D1 is larger than the distance D2 is described as an example, but the same effect can be obtained when the distance D2 is larger than the distance D1. From this point of view, in the present invention, it is preferable to satisfy the numerical range of the above ratio (D1 / D2) in the ratio of the smaller one of the distance D1 and the distance D2 as the denominator and the larger one as the numerator.

In this segment 18, the number of regions of the blade low region Ad is 1. The mold 16 may include only such a segment 18. Also in this case, the periodic rigidity difference can be further alleviated by making the distance D1 and the distance D2 different between one of the adjacent segments 18 and the other.

In this segment 18, the number of regions of the blade low region Ad was 1, but it is not limited to this. A plurality of blade low region Ad may be formed in the segment 18 by changing the position in the circumferential direction. Also in this case, in each blade low region Ad, the distance D1 to the blade low region Ap or the blade low region Ad adjacent to one in the circumferential direction and the blade low region Ap or the blade low region Ad adjacent to the other in the circumferential direction are reached. It is preferable that the distance D2 is different from that of.

The mold 16 having a large number of regions of the blade low region Ad contributes to alleviating the periodic rigidity difference in the circumferential direction of the tire. The mold 16 can make the RFV smaller. From the viewpoint of improving this RFV, the number of regions of the blade low region Ad formed in each segment 18 is preferably 1 or more, more preferably 2 or more, and particularly preferably 3 or more.

On the other hand, the grip performance can be improved by deepening the sipes formed by the blades. From the viewpoint of this grip performance, the number of regions of the blade low region Ad formed in each segment 18 is preferably 10 or less, more preferably 8 or less, and particularly preferably 6 or less.

In this mold 16, the number of regions of the blade low region Ad of the adjacent segments 18 may be different. For example, these segments 18 may be composed of two or more types of segments 18 having different numbers of blade low region Ad regions, or may be composed of nine types of segments 18 having different numbers of blade low region Ad regions. Further, in the mold 16 in which a plurality of types of segments 18 are combined, those segments 18 may include those in which the blade low region Ad is not formed.

Further, the mold 16 having a low Hs at the height of the low back portion 42 is excellent in durability. From this viewpoint, the ratio of height Hs to height Hh (Hs / Hh) is preferably 0.7 or less, and more preferably 0.5 or less . On the other hand, the mold 16 having a high height Hs of the low back portion 42 alleviates the difference in rigidity in the circumferential direction. This mitigation contributes to the improvement of RFV. Further, the mold 16 contributes to the improvement of grip performance. From the viewpoint of RFV and grip performance, this ratio (Hs / Hh) is preferably 0.2 or more, and more preferably 0.3 or more.

The blade low region Ad extends from one end to the other in the axial direction on the inner surface 24 forming the tread surface, but is not limited to this. The blade low region Ad may be partially formed on any or two or more of the inner surface 24, near one end in the axial direction, near the equatorial plane, and near the other in the axial direction. Even if it is formed in this way, the difference in the periodic rigidity of the tire can be alleviated.

Further, the low back portion 42 may be randomly scattered in the non-split position region without forming the blade low region Ad. Even if it is formed in this way, the periodic rigidity difference of the tire can be alleviated.

Hereinafter, the effects of the present invention will be clarified by Examples, but the present invention should not be construed in a limited manner based on the description of these Examples.

[Example 1]
A mold having the basic structure shown in FIG. 1-6 was prepared. This mold has 9 segments. The number of regions of the blade low region Ad formed in each segment was 0 to 10. Twenty tires were manufactured using this mold. This tire size was 185 / 60R15.

[Comparative Example 1]
A mold similar to that of Example 1 was prepared except that the blade low region Ad was not formed. This mold is a conventional mold. Twenty tires were manufactured using this mold.

[Example 2]
A mold was prepared in the same manner as the mold of Example 1 except that the number of regions of the blade low region Ad formed in each segment was changed from 11 to 15. Twenty tires were manufactured using this mold.

[RFV]
Radial force variation was measured under the conditions shown below in accordance with the uniformity test method specified in "JASO C607: 2000". The results of measuring 20 tires each are shown in the "RFV9H" column of Table 1. "RFV9H" represents the measurement result of the ninth-order component of RFV. In this evaluation result, "A" is the best, "D" is the worst, and "A", "B", "C", and "D" are preferable in this order.
Internal pressure: 200 kPa
Load: 4.21kN
Speed: 60 rpm

[Performance on ice]
Each tire was mounted on a vehicle and its grip performance on ice was evaluated. The results are shown in Table 1. In this evaluation result, "A" is the best, "D" is the worst, and "A", "B", "C", and "D" are preferable in this order.

As shown in Table 1, the examples have a higher evaluation than the comparative examples. From this evaluation result, the superiority of the present invention is clear.

The mold described above can be applied to the manufacture of various tires having sipes.

16 ... Mold 18 ... Segment 24 ... Inner surface 30 ... Main body 32 ... Blade 34, 48 ... Protrusions 36 ... Bottom surface 38 ... Main blade 40 ... Secondary blade 42 ... Low back 44 ... Main body 50 ... Recess

Claims (5)

A mold for vulcanizing and molding tires.
Arranged in the circumferential direction, it has multiple segments that form the tread surface of the tire.
The above segment comprises a main blade and a secondary blade that form a sipe.
The secondary blade, at least in part thereof, has a low back portion whose height is lower than the height of the main blade.
The low back portion is arranged in the non-split position region of the segment,
A plurality of the low back portions are arranged, and the low back portions are gathered to form a blade low region where the height of the blade is low.
The blade low region is divided into a split position region and a non-split position region of the segment with a region formed by arranging and gathering main blades having a height higher than the low back portion in the circumferential direction in the circumferential direction. Formed at intervals in the circumferential direction ,
A tire mold in which the blade low region formed in the split position region of the segment is formed so as to straddle the segments adjacent to each other in the circumferential direction including the split position . In a state where multiple segments are arranged in the circumferential direction to form a ring,
When the distance between the blade low region and the blade low region adjacent to one in the circumferential direction is D1 and the distance from the blade low region adjacent to the other in the circumferential direction is D2, the distance D1 in each blade low region. The mold according to claim 1, wherein the distance D2 is different from that of the above distance D2. The mold according to claim 1 or 2, wherein the number of regions of the blade low region formed in each segment is 10 or less. Claims 1 to 3 in which the ratio of the height Hs to the height Hh is 0.7 or less when the height of the main blade is Hh and the height of the blade at the low back is Hs. The mold described in any of. A tire in which a sipe is formed on the tread in multiple segments divided in the circumferential direction.
The sipe consists of a main sipe and a sub sipe, and the sub sipe has at least a part of it having a shallow depth that is shallower than the main sipe.
The shallow depth portion is formed in a non-parting line region corresponding to the non-parting position region of the segment, and a plurality of the shallow depth portions are gathered to form a sipe shallow region in which the sipe depth is shallow.
The shallow region of the sipes is divided into a parting line region and a non-parting line region corresponding to the split position region of the segment, with the region formed by arranging and gathering the main sipes in the circumferential direction in the circumferential direction. Formed at intervals in the circumferential direction ,
A tire in which the shallow sipe region formed in the parting line region is a region including the parting line and formed over adjacent segments in the circumferential direction .

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