JP5679105B2 - Pneumatic tire and its vulcanization mold - Google Patents

Description

  The present invention relates to a pneumatic tire used for a four-wheeled vehicle, a truck, a bus, and the like and a mold for vulcanization thereof, and in particular, a pneumatic tire used for running on a snowy road and running on a wet road surface. And a mold for vulcanization thereof.

  Generally, pneumatic tires for snowy roads include a plurality of circumferential grooves provided in the tread portion, a plurality of width direction grooves provided in the tread portion, and a plurality of land formed in the tread portion by each groove. Are provided, and a plurality of sipes are provided on each land portion (see, for example, Patent Document 1).

  Moreover, as a pneumatic tire for preventing stone biting into the groove, a plurality of circumferential grooves provided in the tread part, a plurality of width direction grooves provided in the tread part, and each groove are formed in the tread part. It is known that a plurality of land portions and a plurality of protrusions arranged in parallel in each circumferential groove are provided, and stone protrusions into the circumferential groove are prevented by each protrusion (for example, Patent Documents) 2).

JP 2008-221955 A JP 2006-056480 A

  In the pneumatic tire, in order to improve the running performance on a snowy road or a wet road surface, it is generally preferable to increase the groove width of each circumferential groove or the width direction groove, and the running performance on a dry road is improved. In order to improve, it is generally preferable to increase the land area by reducing the groove width of each circumferential groove and width direction groove, and the requirements of the groove width for both characteristics are different. It is often set to an appropriate groove width in consideration. Further, in many cases, improvement in running performance on snowy roads and wet roads is devised by devising tread patterns and sipe shapes provided on land.

  In the latter pneumatic tire, a plurality of protrusions are juxtaposed in each circumferential groove, and pebbles enter each circumferential groove by providing a plurality of protrusions as obstacles in each groove. Is preventing. In addition, each protrusion is formed in a hexagonal prism shape to prevent pebbles from entering each circumferential groove, and each protrusion is 20 to 50% higher than the depth of the circumferential groove. Have

  By the way, when water exists between the ground contact surface of the tread portion of the tire and the hard road surface, such as when the tire travels on a wet road surface, in general, the water is separated from each circumferential groove or width direction groove. In the circumferential groove, water moves in the tire traveling direction, and the water that has moved to the outside of the grounding surface is drained from the circumferential groove and the widthwise groove, so that water is discharged from the tire grounding surface. It has come to be.

  For this reason, as in the latter pneumatic tire, when a plurality of protrusions having the shape and height are provided in each circumferential groove, the movement of water in the circumferential groove is hindered, and the wet road surface of the tire is Driving performance is reduced. In other words, it can be said that the latter pneumatic tire causes a decrease in running performance on a wet road surface in order to improve the stone biting prevention effect.

  The present invention has been made in view of the above problems, and the object of the present invention is to improve the running performance on a wet road surface and to improve the running performance on a snowy road. The object is to provide a pneumatic tire and a mold for vulcanization thereof.

For the present invention, to attain the aforementioned object, a plurality of grooves provided in the tread portion, the pneumatic tire having a groove to thus plurality of land portions formed in the tread portion of the plurality of, in said groove A plurality of protrusions arranged in parallel in the extending direction of the groove portion, each protrusion is formed so as to protrude outward in the tire radial direction from the bottom surface of the groove portion, and is disposed apart from the side surface of the groove portion. One side curved surface portion of the convex curved surface, the height from the groove bottom surface gradually increasing from one side to the other in the extending direction, and the height from the groove bottom surface gradually from one side to the other in the groove portion extending direction The other curved surface portion of the convex curved surface, the one side wall portion which is provided on the center side of the protrusion in the groove extending direction and forms an angle of 120 ° or less with the one curved surface portion, and the center of the protrusion in the groove extending direction. The other side curved surface provided on the side Possess and the other side wall portion forming an angle of 120 ° or less, the groove has a plurality of circumferential grooves extending in the tire circumferential direction with aligned in the tire width directions, arranged in a certain circumferential direction groove The plurality of protrusions formed are formed such that the area of each protrusion when viewed from the tire radial direction is larger on the center side in the tire width direction than on the outer side in the tire width direction.

In order to achieve the above object, the present invention provides a pneumatic tire having a plurality of groove portions provided in a tread portion and a plurality of land portions formed in the tread portion by the plurality of groove portions. A plurality of protrusions arranged side by side in the extending direction of the groove portion, each protrusion is formed so as to protrude outward in the tire radial direction from the bottom surface of the groove portion, and is disposed apart from the side surface of the groove portion, One side curved surface portion of the convex curved surface whose height from the groove portion bottom surface gradually increases from one to the other in the extending direction of the groove portion, and the height from the groove portion bottom surface gradually from one to the other in the groove portion extending direction The curved surface on the other side of the convex curved surface, the one side wall portion which is provided on the center side in the groove extending direction in the protrusion and forms an angle of 120 ° or less with the one curved surface section, and the groove extending direction in the protrusion. The other side is provided at the center side The groove portion has a plurality of circumferential groove portions that are aligned with each other in the tire width direction and extend in the tire circumferential direction, and each groove portion in the circumferential groove portion has an angle of 120 ° or less and the other side wall portion. When the projections provided on the center side in the tire width direction are viewed from the outer side in the tire radial direction than the projections in the circumferential groove provided on the outer side in the tire width direction, Is formed so as to have a large area.

  In this way, a plurality of protrusions are arranged in parallel in the groove portion of the tread portion, and each protrusion is formed so as to protrude outward in the tire radial direction from the bottom surface of the groove portion, and from one side to the other in the extending direction of the groove portion. One side curved surface portion of the convex curved surface that gradually increases in height from the groove bottom surface, and the other curved surface of the convex curved surface that gradually decreases in height from the groove bottom surface toward one side in the extending direction of the groove portion For example, when the groove provided with each protrusion is a circumferential groove extending in the tire circumferential direction, the tire travels on a wet road surface, and water travels in the circumferential groove from one side in the circumferential direction of the tire. When moving toward the other side, for example, one curved surface portion comes into contact with the water coming toward each projection, and, for example, the other curved surface portion comes into contact with water moving away from each projection.

  Here, the one-side curved surface portion is a convex curved surface whose height from the bottom surface of the groove portion gradually increases from one side to the other in the extending direction of the groove portion. Can move smoothly in the tire circumferential direction. In addition, the other curved surface portion is a convex curved surface in which the height from the bottom surface of the groove portion gradually decreases from one to the other in the extending direction of the groove portion. The one-side curved surface portion is a convex curved surface whose height from the bottom surface of the groove portion gradually increases from one to the other in the extending direction of the groove portion, so that it moves in the circumferential groove portion. Each protrusion acts so as to change the water flow direction to the outer side in the tire radial direction, and the water that has moved in the circumferential groove to the outside of the ground contact surface is easily discharged from the circumferential groove. Therefore, by providing each protrusion having the one-side curved surface portion and the other-side curved surface portion, it is possible to ensure smooth movement of water in the groove portion and to promote discharge from the circumferential groove portion of the water moved to the outside of the ground surface. It becomes.

  Each protrusion is provided on the center side in the groove extending direction of the protrusion and forms one side wall portion forming an angle of 120 ° or less with the one side curved surface part, and on the center side of the protrusion in the groove extending direction. A side curved surface portion and the other side wall portion forming an angle of 120 ° or less are provided. For this reason, when the tire travels on a snowy road, an edge at each boundary between the wall part and each curved surface part or each wall part itself bites into the snow on the snowy road.

In general, the tire tends to have a greater distortion during running on the outer side in the width direction than on the center side in the width direction, but in the present invention, when viewed from the tire radial direction of each protrusion in each circumferential groove portion, Is larger on the center side in the tire width direction than on the outer side in the tire width direction, so a small protrusion is arranged on the side with a large distortion during traveling, and a large protrusion on the side with a small distortion during traveling Be placed.

Thus, according to the present invention, when the tire travels on a wet road surface, it is possible to ensure smooth movement of water in the groove portion and promote discharge from the water groove portion that has moved to the outside of the ground surface, When the tire travels on a snowy road, the edges at the boundary between each wall and each curved surface part and each wall itself bite into the snow on the snowy road, so it is possible to improve the running performance on wet roads. , yet it is possible to achieve also improvement of the running performance on snow-covered road. Furthermore, since small protrusions are arranged on the side with large distortion during traveling and large protrusions are disposed on the side with small distortion during traveling, cracks that can occur in the circumferential groove due to stress concentration at the position of the protrusions Can be prevented as much as possible.

The principal part front view of the pneumatic tire of the 1st premise technique of the present invention Front view of main parts of pneumatic tire AA line sectional view in FIG. BB sectional view in FIG. CC sectional view in FIG. View of protrusions seen from the tire radial direction Perspective view of main part of pneumatic tire Operation diagram of pneumatic tire The figure which shows the 1st modification of protrusion The figure which shows the 2nd modification of protrusion The principal part front view of the pneumatic tire of 1st Embodiment of this invention. The principal part front view of the pneumatic tire of 2nd Embodiment of this invention. The principal part front view of the pneumatic tire of the 2nd assumption technology of the present invention The principal part front view of the pneumatic tire of the 3rd premise technique of the present invention The figure which shows the 3rd modification of protrusion The figure which shows the 4th modification of protrusion The figure which shows the 5th modification of protrusion The figure which shows the 6th modification of protrusion The figure which shows the 7th modification of protrusion The figure which shows the 8th modification of protrusion The figure which shows the 9th modification of protrusion The principal part front view of the pneumatic tire which shows the modification of 1st basic technology Table showing evaluation results Table showing evaluation results Table showing evaluation results

A pneumatic tire according to a first prerequisite technology of the present invention will be described with reference to FIGS. This pneumatic tire is used by being mounted on a vehicle such as a four-wheeled vehicle, a truck, or a bus.

In this pneumatic tire, a plurality of circumferential groove portions 2 and a plurality of width direction groove portions 3 are provided in the tread portion 1, and a plurality of land portions 4 are formed in the tread portion 1 by providing the groove portions 2 and 3. The land portion 4 is provided with a plurality of known sipes 5. The tire of the base technology is an ice and snow tire. In the base technology , two circumferential grooves 2 are provided on one side in the width direction with respect to the center CL in the width direction of the tire, and two circumferential grooves are provided on the other side in the width direction.

The depth D0 of each circumferential groove 2 is, for example, 10 mm, and the width W0 is also 10 mm, but other depths and width dimensions can also be adopted. The width W0 of each circumferential groove 2 is the distance between the tops of the grooves 2 (see FIG. 4). Each circumferential groove 2 is provided so as to extend in the circumferential direction of the tire. In the base technology , each circumferential groove 2 extends linearly in the circumferential direction of the tire.

The depth D0 of each width direction groove portion 3 is, for example, 10 mm, and the width W0 is also 10 mm. However, other depths and width dimensions can be adopted. In addition, the width W0 of each width direction groove part 3 is the distance between the top parts of the groove part 3 (refer FIG. 5). Each width direction groove 3 extends in the tire width direction (the direction of the tire rotation center axis RA), and the angle formed by each width direction groove 3 with the tire rotation center axis RA is approximately 35 °. In each premise technique of this specification, when the angle which each width direction groove part 3 makes with rotation center axis RC of a tire is 50 degrees or less, width direction groove part 3 is extended in the width direction of a tire. And

  A plurality of protrusions 10 are provided in each of the groove portions 2 and 3 so as to be aligned in the extending direction of the groove portions 2 and 3. Each protrusion 10 is formed so as to protrude outward in the tire radial direction from the bottom surface 2a, 3a of each groove portion 2, 3, and is spaced apart from the side surface 2b, 3b of each groove portion 2, 3 (FIG. 1). ~ 5).

Each protrusion 10 includes a convex curved one-side curved surface portion 10a in which the height from the bottom surface 2a, 3a gradually increases from one to the other in the extending direction of each groove portion 2, 3, and each groove portion 2, 3 The other side curved surface portions 2b and 3b gradually decrease in height from the bottom surfaces 2a and 3a from one side to the other in the extending direction. Each curved surface portion 2a, 3a, 2b, 3b is a convex curved surface even in a section along the extending direction of each groove portion 2, 3, and even in a cross section perpendicular to the extending direction of each groove portion 2, 3. It is a convex curved surface (see FIGS. 3 to 5). Further, each projection 10 is provided on the center side in the extending direction of the groove portions 2 and 3 in the projection 10, and one side wall portion 10 c in which the angle β formed with the one-side curved surface portion 10 a is approximately 95 °, and the projection 10 It has the other side wall part 10d which is provided in the center side of the extending direction of the groove parts 2 and 3, and makes the angle (gamma) which makes with the other side curved surface part 10b substantially 95 degrees (refer FIG.3 and FIG.7). Thus, each projection 10 is formed by a set of one side projection having one side curved surface portion 10a and one side wall portion 10c, and the other side projection having the other side curved surface portion 10b and the other side wall portion 10d. . Further, each protrusion 10 is formed to have a length in the extending direction of each groove 2, 3. Furthermore, in the base technology , the one-side projection itself having the one-side curved surface portion 10a and the one side wall portion 10c is also formed to have a length in the extending direction of the groove portions 2 and 3, and the other-side curved surface portion 10b and the other side The other side projection itself having the side wall portion 10d is also formed to have a length in the extending direction of the groove portions 2 and 3.

  The angles β and γ are preferably 120 ° or less, and more preferably 100 ° or less, in order to improve the following bite property to snow. The angle β formed by the one side curved surface portion 10a and the one side wall portion 10c may be 120 ° or less or 100 ° or less at least near the top of the one side wall portion 10c. It is preferable that it is about 120 degrees or less or 100 degrees or less over the whole boundary part with the part 10c. Similarly, the angle γ formed between the other side curved surface portion 10b and the other side wall portion 10d may be 120 ° or less or 100 ° or less at least near the top of the other side wall portion 10d, but preferably the other side curved surface portion 10c. It is preferable that it is about 120 degrees or less or 100 degrees or less over the whole boundary part with 10d of other side walls.

In the base technology , as shown in FIG. 3, the height H of each protrusion 10 is approximately 1 mm. The distance L between the top of one side wall 10c and the top of the other side wall 10d of each projection 10 is approximately 1 mm. Further, as shown in FIG. 6, when each protrusion 10 is viewed from the tire radial direction, the area occupied by the one-side curved surface portion 10c and the other-side curved surface portion 10d is the entire area of the protrusion 10 (the hatched portion in FIG. 6). The width dimension W of each protrusion 10 is approximately 2.5 mm.

  Further, as shown in FIG. 2 and the like, when each protrusion 10 is viewed from the tire radial direction, one end in the extending direction of each of the groove portions 2 and 3 in the protrusion 10 faces one of the extending directions. The other end in the extending direction of each of the groove portions 2 and 3 in the protrusion 10 is a protruding shape formed in a curve toward the other in the extending direction.

  Further, as shown in FIG. 2 and the like, the protrusions 10 adjacent to each other in the extending direction of the grooves 2 and 3 are arranged so that the positions thereof are different in the width direction of the grooves 2 and 3. In addition, a predetermined number of protrusions adjacent to each other in the extending direction of the groove portions 2 and 3 from one to the other in the extending direction of the groove portions 2 and 3 from one to the other in the width direction of the groove portions 2 and 3. It is arranged so that the position gradually shifts. For example, as shown in FIG. 2, each protrusion 10 of each circumferential groove 2 has three protrusions 10 adjacent to each other so that the circumferential groove 2 has an extension from one side to the other in the extending direction of the circumferential groove 2. The protrusions 10 of the width direction groove portion 3 are arranged so that two or three protrusions 10 adjacent to each other have a width different from each other in the width direction (from left to right in FIG. 2). The direction groove part 3 is disposed so that the position is shifted from one side to the other side in the width direction of the width direction groove part 3 from one side to the other side in the extending direction.

  The cavity of the vulcanization mold for vulcanizing and molding the pneumatic tire has irregularities corresponding to each circumferential groove 2, each width groove 3, each land 4, each sipe 5, and each projection 10. The circumferential grooves 2, the widthwise grooves 3, the land portions 4, the sipes 5, and the protrusions 10 are engraved on the tread portion 1 of the tire.

  As shown in FIG. 8, the pneumatic tire configured as described above travels on a wet road surface, and water exists between the ground contact surface CA of the tread portion 1 of the tire and a hard road surface HR such as an asphalt road. In this case, the water enters each circumferential groove 2 and each width groove 3, and the water moves in the circumferential direction of the tire 2 in the circumferential groove 2, and the water that has moved to the outside of the contact surface CA is By draining from the direction groove part 2 and each width direction groove part 3, water is discharged | emitted from the contact surface CA of a tire.

Here, in the base technology , a plurality of protrusions 10 are arranged in parallel in each circumferential groove 2 in the tread portion 1, and each protrusion 10 is formed so as to protrude outward in the tire radial direction from the bottom surface 2 a of the circumferential groove 2. In addition, the one-side curved surface portion 10a of the convex curved surface whose height from the bottom surface 2a gradually increases from one side to the other in the extending direction of the circumferential groove portion 2 and one of the extending direction of the circumferential groove portion 2 And the other curved surface portion 10b of the convex curved surface, the height of which gradually decreases from the bottom surface 2a toward the other. Therefore, when the tire travels on a wet road surface and water moves in each circumferential groove portion 2 from one side to the other side in the extending direction, as shown in FIG. The one-side curved surface portion 10a comes into contact with water, and the other-side curved surface portion 10b comes into contact with water moving in the away direction.

  Here, the one-side curved surface portion 10a is a convex curved surface in which the height from the bottom surface 2a gradually increases from one side to the other in the extending direction of the circumferential groove portion 2, so Water can smoothly move in the tire circumferential direction within the directional groove 2. Further, the other curved surface portion 10b is a convex curved surface whose height from the bottom surface 2a gradually decreases from one to the other in the extending direction of the circumferential groove portion 2, and thus occurs in the water that has passed through each protrusion 10. Turbulent flow can be reduced, and the one-side curved surface portion 10a is a convex curved surface whose height from the bottom surface 2a gradually increases from one to the other in the extending direction of the circumferential groove portion 2. Then, each protrusion 10 acts so as to change the flow direction of the water moving in the circumferential groove portion 2 to the outer side in the tire radial direction, and the water moved in the circumferential groove portion 2 to the outside of the ground contact surface CA is the circumferential groove portion. 2 is easily discharged. Therefore, by providing each protrusion 10 having the one-side curved surface portion 10a and the other-side curved surface portion 10b, it is possible to ensure the smooth movement of water in the circumferential groove portion 2 and the circumferential groove portion of the water moved to the outside of the ground contact surface CA. The emission from 2 can be promoted.

  Further, each protrusion 10 is provided on the center side in the extending direction of the circumferential groove 2 in the protrusion 10, one side wall 10 c that forms an angle of approximately 95 ° with the one-side curved surface 10 a, and the circumferential groove in the protrusion 10. The other side wall portion 10d is provided on the center side in the extending direction 2 and forms an angle of approximately 95 ° with the other curved surface portion 10d. For this reason, when the tire travels on a snowy road, the edges at the boundaries between the wall parts 10c and 10d and the curved surface parts 10a and 10b and the wall parts 10c and 10d themselves bite into the snow on the snowy road.

For this reason, this base technology can improve the running performance on wet road surfaces, and can also improve the running performance on snowy roads.

Further, the base technology is such that each projection 10 has a convex curved one-side curved surface portion 10a in which the height from the bottom surface 2a gradually increases from one to the other in the extending direction of the circumferential groove portion 2, and the circumferential groove portion. 2 and the other curved surface portion 10b of the convex curved surface whose height from the bottom surface 2a gradually decreases from one to the other in the extending direction, so that the tire rotates in any direction as described above. Has the effect of.

  On the other hand, each protrusion 10 provided in each widthwise groove 3 is also formed so that each protrusion 10 protrudes from the bottom surface 3a of the widthwise groove 3 outward in the tire radial direction, and the widthwise groove 3 extends. One side curved surface portion 10a of the convex curved surface whose height from the bottom surface 3a gradually increases from one side to the other in the direction, and from the bottom surface 3a gradually from one side to the other in the extending direction of the width direction groove portion 3. And the other curved surface portion 10b of the convex curved surface having a low height. For this reason, when the tire travels on the wet road surface and the water moves in each width direction groove portion 3 from one side to the other side in the width direction of the tire, for example, one side is in contact with the water coming toward each projection 10. It becomes the curved surface portion 10a, and the other curved surface portion 10b comes into contact with the water moving in the away direction.

  Here, the one-side curved surface portion 10a is a convex curved surface in which the height from the bottom surface 3a gradually increases from one side to the other in the extending direction of the widthwise groove portion 3, so Water can smoothly move in the tire circumferential direction in the direction groove portion 3. Further, the other curved surface portion 10b is a convex curved surface whose height from the bottom surface 3a gradually decreases from one side to the other in the extending direction of the widthwise groove portion 3, and thus occurs in the water that has passed through each projection 10. The turbulent flow can be reduced, and the one-side curved surface portion 10a is a convex curved surface whose height from the bottom surface 3a gradually increases from one side to the other in the extending direction of the widthwise groove portion 3. Then, each protrusion 10 acts so as to change the flow direction of the water moving in the width direction groove portion 3 to the outer side in the tire radial direction, and the water moved in the width direction groove portion 3 to the outside of the ground contact surface CA becomes the width direction groove portion. 3 is easily discharged. Therefore, by providing each protrusion 10 having the one-side curved surface portion 10a and the other-side curved surface portion 10b, it is possible to ensure smooth movement of water in the widthwise groove portion 3 and to promote drainage from the widthwise groove portion 3. .

  Each protrusion 10 is provided on the center side in the extending direction of the widthwise groove 3 in the protrusion 10 and has one side wall 10c that forms an angle of approximately 95 ° with the one-side curved surface 10a, and the widthwise groove in the protrusion 10. 3 is provided on the center side in the extending direction 3 and the other side wall portion 10d that forms an angle of approximately 95 ° with the other curved surface portion 10d. For this reason, when the tire travels on a snowy road, the edges at the boundaries between the wall portions 10c, 10d and the curved surface portions 10a, 10b and the wall portions 10c, 10d themselves bite into the snow on the snow road, This is advantageous in improving the grip force in the tire width direction with respect to the snowy road.

In the base technology , as shown in FIGS. 3 to 5, the curved surface portions 10 a and 10 b are convex curved surfaces even in the cross section in the direction along the extending direction of the groove portions 2 and 3. Even the cross section in the direction orthogonal to the extending direction 3 is a convex curved surface. For this reason, it is possible to efficiently ensure smooth movement of water in the groove portions 2 and 3 and promote drainage from the groove portions 2 and 3.

In the base technology , the entire curved surface portions 10a and 10b are convex curved surfaces in a section along the extending direction of the groove portions 2 and 3, and the extending direction of the groove portions 2 and 3 is the same. The cross section in the direction perpendicular to the surface is also a convex curved surface. A modification to this is shown in FIG. 9A is a view of the protrusion 10 viewed from the tire radial direction, FIG. 9B is a cross-sectional view taken along the line DD in FIG. 9A, and FIG. 9C is FIG. It is the EE sectional view taken on the line in (). As shown in FIGS. 9A to 9C, one side of the groove portion extending direction of the one-side curved surface portion 10a is divided into both a section along the groove portion extending direction and a section perpendicular to the groove portion extending direction. It is formed to be a convex curved surface, and the other side of the groove portion extending direction of the other side curved surface portion 10b is both in a cross section along the groove portion extending direction and a cross section in a direction perpendicular to the groove portion extending direction in the groove portion extending direction. It forms so that it may become a convex curve, and it forms so that the other side of the groove part extension direction of the one side curved surface part 10a may become a convex curve only in the cross section of the direction orthogonal to a groove part extension direction, and the other side curved surface part 10b It is also possible to form one side of the groove extending direction so as to be a convex curved surface only in a cross section in a direction orthogonal to the groove extending direction. Each protrusion 10 in each width direction groove part 3 can be formed similarly. Even when the projections 10 as shown in FIG. 9 are provided, the curved surface portions 10 a and 10 b are also convex curved surfaces in the cross section in the direction along the extending direction of the groove portions 2 and 3. Since the cross section in the direction orthogonal to the installation direction is also a convex curved surface, it is possible to efficiently ensure the smooth movement of water in the grooves 2 and 3 and promote drainage from each groove 2 and 3. Become.

Further, in the base technology , the distance L in the extending direction of the groove portions 2 and 3 between the one side wall portion 10c and the other side wall portion 10d in each protrusion 10 is 1 mm, and the height H of each protrusion 10 is 1 mm. . That is, the distance L between the one side wall part 10 c and the other side wall part 10 d in each protrusion 10 is one time the height H of each protrusion 10. For this reason, as described above, when the one side curved surface portion 10a comes into contact with the water coming toward each projection 10, the one side wall portion 10b comes into contact with the water moving in the direction away from the one side wall portion. Since the distance L between 10c and the other side wall portion 10d is smaller than the height H of the protrusion 10, no large turbulent flow occurs at the distance L between the one side wall portion 10c and the other side wall portion 10d. In addition, if the space | interval L of the one side wall part 10c and the other side wall part 10d is 3 times or less with respect to the height H of each protrusion 10, the same effect can be show | played. Further, as shown in FIG. 3, the interval L is the interval between the top of one side wall 10c and the top of the other side wall 10d.

In the base technology , when each protrusion 10 is viewed from the tire radial direction, the range occupied by the one-side curved surface portion 10a and the other-side curved surface portion 10b is 70% or more of the entire protrusion 10. For this reason, it is possible to efficiently ensure smooth movement of water in each of the grooves 2 and 3 and promote drainage from the grooves 2 and 3. In addition, if the range which the one side curved surface part 10a and the other side curved surface part 10b occupy when each protrusion 10 is seen from the tire radial direction is 50% or more of the entire protrusion 10, the same effect can be obtained.

In the base technology , when each protrusion 10 is viewed from the tire radial direction, one end and the other end of each protrusion 10 in the extending direction of each groove 2, 3 are directed in the extending direction of each groove 2, 3. It is a convex shape consisting of curved lines. For this reason, it is possible to efficiently ensure smooth movement of water in each of the grooves 2 and 3 and promote drainage from the grooves 2 and 3. As shown in FIG. 10, even when one end and the other end of each protrusion 10 in the extending direction of each groove 2, 3 have a convex shape using a straight line toward the extending direction of each groove 2, 3. The same effects can be obtained.

Further, in the base technology , the protrusions 10 adjacent to each other are arranged at different positions in the width direction of the groove portions 2 and 3. For this reason, in each width direction position in each groove part 2, 3, the flow direction of the water which moves the inside of each groove part 2, 3 in the extending direction can be changed to the tire radial direction outer side, The drainage from 3 can be promoted efficiently.

In the base technology , a predetermined number of adjacent protrusions are gradually displaced from one side to the other side in the width direction of the groove portions 2 and 3 from one side to the other side in the extending direction of the groove portions 2 and 3. Are arranged as follows. For this reason, the flow direction of the water that moves in the extending direction in each of the groove portions 2 and 3 in order from one side in the width direction in each of the groove portions 2 and 3 can be changed outward in the tire radial direction. , 3 can efficiently promote drainage.

In the base technology , each protrusion 10 is formed to have a length in the extending direction of each groove 2, 3. This configuration is advantageous in ensuring smooth movement of water in each of the grooves 2 and 3, and is also advantageous in efficiently draining water from the tire contact surface CA.

Further, in the base technology , the one-side projection itself composed of the one-side curved surface portion 10a and the one-side wall portion 10c is also formed to have a length in the extending direction of the groove portions 2 and 3, and the other-side curved surface portion 10b and the other side The other side projection itself composed of the side wall portion 10d is also formed to have a length in the extending direction of the groove portions 2 and 3. This configuration is advantageous in ensuring smooth movement of water in each of the grooves 2 and 3, and is also advantageous in efficiently draining water from the tire contact surface CA.

Further, in this base technology , each protrusion 10 is disposed away from the side surfaces 2b, 3b of each groove 2, 3 and the height H of each protrusion 10 is low, so that the water in each groove 2, 3 is smooth. This is advantageous in ensuring movement.

A pneumatic tire according to a first embodiment of the present invention will be described with reference to FIG. In addition, the same code | symbol is attached | subjected and shown to the component equivalent to 1st Embodiment.

This pneumatic tire has a plurality of different sizes of each protrusion 10 in the first prerequisite technology . Specifically, as shown in FIG. 11, the area of each of the plurality of protrusions 10 arranged in each circumferential groove 2 when viewed from the tire radial direction is larger than the tire width direction outside the tire width direction. The center side in the direction (side closer to the center CL in the width direction) is larger.

Even in this case, as in the case of the first prerequisite technology , it is possible to ensure the smooth movement of water in each of the grooves 2 and 3 and promote the discharge of water moving in the extending direction of each of the grooves 2 and 3. Since the edges at the boundaries between the walls 10c and 10d and the curved surfaces 10a and 10b and the walls 10c and 10d themselves bite into the snow on the snowy road, it is possible to improve the running performance on wet road surfaces. In addition, driving performance on snowy roads can be improved.

Here, in general, a tire tends to have a greater distortion during traveling on the outer side in the width direction than on the center side in the width direction. Moreover, in 1st Embodiment, the area at the time of seeing each protrusion 10 from the tire radial direction in each circumferential direction groove part 2 is larger in the center side of a tire width direction rather than the outer side of a tire width direction. . That is, in the circumferential groove portion 2, the small protrusion 10 is arranged on the side where the distortion during traveling is large and the large protrusion 10 is disposed on the side where the distortion during traveling is small, so that stress concentrates on the position of the protrusion 10. By doing so, cracks that can occur in the circumferential groove 2 can be prevented as much as possible.

  When the size of the protrusion 10 is changed, the height and width can be reduced without changing the dimension of the protrusion 10 in the groove extending direction, and the groove portion can be changed without changing the height of the protrusion 10. The dimension in the extending direction and the width dimension can be reduced, can be reduced as a whole, and can be reduced by other patterns.

A pneumatic tire according to a second embodiment of the present invention will be described with reference to FIG. In addition, the same code | symbol is attached | subjected and shown to the component equivalent to 1st Embodiment.

This pneumatic tire is obtained by changing the arrangement of the protrusions 10 in the first base technology in which there are a plurality of sizes of the protrusions 10. Specifically, as shown in FIG. 12, it is provided on the tire width direction center side (side closer to the width direction center CL) than each protrusion 10 in the circumferential groove portion 2 provided on the outer side in the tire width direction. Each protrusion 10 in the circumferential groove 2 has a larger area of each protrusion 10 when viewed from the outer side in the tire radial direction. In each of the groove portions 2 and 3, two protrusions 10 and a single protrusion 10 arranged in the groove width direction are alternately provided in the extending direction of the groove portions 2 and 3. Even when arranged in this way, the protrusions 10 adjacent to each other in the extending direction of the grooves 2 and 3 are in a state of being displaced in the width direction of the grooves 2 and 3.

Also in the second embodiment, as in the case of the first base technology , ensuring smooth movement of water in each of the grooves 2 and 3 and facilitating discharge of water moving in the extending direction of each of the grooves 2 and 3 Since the edges at the boundaries between the walls 10c and 10d and the curved surfaces 10a and 10b and the walls 10c and 10d themselves bite into the snow on the snowy road, the running performance on wet roads can be improved. In addition, it is possible to improve driving performance on snowy roads.

In addition, the effect of disposing the protrusions 10 adjacent to each other in the extending direction of the groove portions 2 and 3 while shifting the positions in the width direction of the groove portions 2 and 3 is as described in the first prerequisite technology .

Moreover, in 2nd Embodiment, each protrusion 10 in the circumferential direction groove part 2 provided in the tire width direction center side is more than each protrusion 10 in the circumferential direction groove part 2 provided in the outer side of the tire width direction. The area of each protrusion 10 when viewed from the outside in the tire radial direction is large. For this reason, since the small protrusion 10 is arrange | positioned in the circumferential groove part 2 with a large distortion at the time of driving | running | working and the large protrusion 10 is arrange | positioned in the circumferential groove part 2 with a small distortion at the time of driving | running | working, By concentrating, cracks that may occur in the circumferential groove 2 can be prevented as much as possible.

In the first base technology, the first and second embodiments, the protrusions 10 adjacent to each other in the extending direction of the grooves 2 and 3 are arranged so that the positions do not overlap in the width direction of the grooves 2 and 3. However, it is also possible to arrange the protrusions 10 so that the positions of the protrusions 10 are shifted in the width direction of the grooves 2 and 3 while the protrusions 10 overlap each other in the width direction of the grooves 2 and 3. Even in this case, the effect of disposing the protrusions 10 in the width direction of the groove portions 2 and 3 is as described above.

A pneumatic tire according to the second premise technique of the present invention will be described with reference to FIG. In addition, the same code | symbol is attached | subjected and shown to the component equivalent to a 1st premise technique . This pneumatic tire is obtained by arranging the protrusions 10 side by side in the width direction of the groove portions 2 and 3 in the first base technology without shifting their positions.

Also in the second base technology , as in the case of the first base technology , ensuring smooth movement of water in the grooves 2 and 3 and promoting the discharge of water moving in the extending direction of the grooves 2 and 3 Since the edges at the boundaries between the walls 10c and 10d and the curved surfaces 10a and 10b and the walls 10c and 10d themselves bite into the snow on the snowy road, the running performance on wet roads can be improved. In addition, it is possible to improve driving performance on snowy roads.

A pneumatic tire according to the third premise technique of the present invention will be described with reference to FIG. In addition, the same code | symbol is attached | subjected and shown to the component equivalent to a 1st premise technique . In this pneumatic tire, in the first premise technique , a protrusion 10 disposed at a portion where the circumferential groove 2 and the width groove 3 intersect is inclined with respect to the other protrusion 10 in the tire width direction. It is.

In the third base technology , as in the case of the first base technology , the smooth movement of water in each groove 2, 3 is promoted and the discharge of water moving in the extending direction in each groove 2, 3 is promoted. Since the edges at the boundaries between the walls 10c and 10d and the curved surfaces 10a and 10b and the walls 10c and 10d themselves bite into the snow on the snowy road, the running performance on wet roads can be improved. In addition, it is possible to improve driving performance on snowy roads.

  In addition, since the protrusions 10 arranged at the intersections of the circumferential groove 2 and the widthwise groove 3 are inclined with respect to the other protrusions in the tire width direction, the protrusions 10 flow in the circumferential grooves 2. Water easily enters the widthwise groove 3 and is advantageous in efficiently draining water from the circumferential groove 2.

In each of the prerequisite technologies and the embodiments, each protrusion 10 can be replaced with a protrusion 20 as shown in FIG. The protrusion 20 shown in FIG. 15 includes a convex curved one-side curved surface portion 20a whose height from the bottom surface 2a gradually increases from one to the other in the extending direction of the groove portion 2, and one of the extending directions of the groove portion 2. The other curved surface portion 20b of the convex curved surface whose height gradually decreases from the bottom surface 2a toward the other, and the one curved surface portion 20a provided on the center side in the extending direction of the groove portion 2 in the protrusion 10. One side wall portion 20c having an angle of approximately 95 ° and the other side wall portion 20d provided on the center side in the extending direction of the groove portion 2 in the protrusion 10 and the other side curved surface portion 20b having an angle of approximately 95 °; One side wall 20c and the other side wall 20d are arranged between the block 20e. The block 20e is formed in a prismatic or semicircular columnar shape, and one side wall 20f facing the extending direction of the groove 2 is formed on one side wall surface 20c by one surface of the block 20e. The other side wall surface 20g facing the extending direction of the groove 2 is formed on the other side wall surface 20d by the surface.

Even in this case, as in the case of the first prerequisite technology , it is possible to ensure the smooth movement of water in each of the grooves 2 and 3 and promote the discharge of water moving in the extending direction of each of the grooves 2 and 3. Since the edges at the boundaries between the walls 20c and 20d and the curved surfaces 20a and 20b and the walls 20c and 20d themselves bite into the snow on the snowy road, it is possible to improve the running performance on wet road surfaces. In addition, driving performance on snowy roads can be improved.

  Further, the distance L1 between the one side wall portion 20c and the one side facing wall portion 20f and the distance L2 between the other side wall portion 20d and the other side facing wall portion 20g are not more than three times the height H of the protrusion 20. If, for example, the one curved surface portion 20a is in contact with the water coming toward each protrusion 20, the distance L1 between the one side wall portion 20c and the one side facing wall portion 20f, or the other side wall portion 20d and the other side. A large turbulent flow does not occur at the distance L2 from the opposing wall portion 20g.

Further, in each of the base technologies , each protrusion 10 can be replaced with a protrusion 30 as shown in FIG. The projection 30 shown in FIG. 16 includes a convex curved one-side curved surface portion 30a whose height from the bottom surface 2a gradually increases from one side to the other in the extending direction of the groove portion 2, and one of the extending directions of the groove portion 2 The angle formed between the other curved surface portion 30b, the height of which gradually decreases from the bottom surface 2a toward the other, and the one curved surface portion 30a provided on the center side in the extending direction of the groove portion 2 in the projection 10 is substantially the same. One side wall portion 30c that is 90 ° and the other side wall portion 30d that is provided on the center side in the extending direction of the groove portion 2 in the protrusion 10 and that forms an angle with the other-side curved surface portion 20b is approximately 90 °. Here, the one side wall 30c and the other side wall 30d are formed by providing a hole 30e extending in the tire radial direction on the upper surface of the protrusion 30. In FIG. 16, the hole 30e is formed to be rectangular when viewed from the tire radial direction, but may be formed to be a circle, ellipse, or other shape when viewed from the tire radial direction. Is possible.

Moreover, in each said premise technique and each embodiment, it is also possible to replace each protrusion 10 with the protrusion 40 as shown in FIG. The protrusion 40 shown in FIG. 17 includes a convex curved one-side curved surface portion 40a whose height from the bottom surface 2a gradually increases from one to the other in the extending direction of the groove portion 2, and one of the extending directions of the groove portion 2 The angle formed between the other curved surface portion 40b, the height of which gradually decreases from the bottom surface 2a toward the other side, and the one curved surface portion 40a provided on the center side in the extending direction of the groove portion 2 in the projection 10 is substantially the same. One side wall portion 40c that is 90 °, the other side wall portion 40d that is provided on the center side in the extending direction of the groove portion 2 in the projection 10 and that forms an angle with the other side curved surface portion 40b, and that is one side wall portion 40c and the one side opposing wall part 40e facing the extending direction of the groove part 2, and the other side wall part 40d and the other side wall part 40f facing the extending direction of the groove part 2. Here, the one side wall portion 40c and the one side facing wall portion 40e are formed by providing a hole 40g extending in the tire radial direction on the upper surface of the protrusion 40, and the other side wall portion 40d and the other side opposing wall portion 40f are the upper surface of the protrusion 40. Is formed by providing a hole 40h extending in the tire radial direction. Further, another hole 40i is provided between the holes 40g and 40h. In FIG. 17, the holes 40g, 40h, and 40i are formed so as to have a rectangular shape when viewed from the tire radial direction. However, when viewed from the tire radial direction, the holes 40g, 40h, and 40i have a circle, an ellipse, or other shapes. It is also possible to form.

  In FIG. 16, the length in the extending direction of the groove 2 of the protrusion 30 can be shortened as shown in FIG. Further, as shown in FIG. 19, it is possible to form the protrusion 30 so as to be substantially circular when viewed from the tire radial direction. Further, as shown in FIG. 20, the protrusions 30 can be formed in a polygonal shape such as a rhombus when viewed from the tire radial direction. Further, as shown in FIG. 21, the protrusions 30 can be formed in a star shape when viewed from the tire radial direction.

Moreover, in each said premise technique and each embodiment, as shown in FIG. 22, it is also possible to provide a different protrusion in the position where the circumferential direction groove part 2 and the width direction groove part 3 cross | intersect.

Tire of the first prerequisite technology (Example 1), tire of the first embodiment (Example 2), tire of the second embodiment (Example 3), tire of the second prerequisite technology (Example 4) and comparative example Of tires (tires not provided with the protrusions 10 in the first premise technology ) were investigated, and the results of investigating snow braking performance, snow climbing performance, snow circle turning performance, and circular turning performance on wet road surfaces are shown in FIG. . These tests were carried out by manufacturing tires having a size of 225 / 65R17.

  On the snow braking performance, each tire was evaluated by applying an ABS brake at a traveling speed of 40 km / h on the snow road surface of an outdoor test site and measuring the braking distance until the vehicle stopped. The evaluation is performed 5 times, and the measured values of each of the 5 braking distances are obtained by performing a correction process for correcting the variation in the traveling speed. Among them, the values of the longest braking distance and the shortest braking distance are obtained. The average value of the braking distance for three times excluding the above was obtained and expressed as an index value with the comparative example being 100. The index value indicates that the braking distance is shorter as the value increases.

  The snow climbing performance was expressed as an index value with a comparative example of 100, in which the startability was evaluated based on the sensory evaluation of the driver on a snowy slope uphill with an inclination of 4 °. The exponent value indicates that the larger the numerical value, the better the startability.

  The circular turning performance on snow was expressed as an index value with a comparative example of 100, in which the turning performance was evaluated based on the sensory evaluation of the driver on a flat snowy road surface. The index value indicates that the turning performance is better as the numerical value is larger.

  The circular turning performance on a wet road surface was expressed as an index value with a comparative example of 100, in which the turning performance on a flat wet road surface was evaluated based on the sensory evaluation of the driver. The index value indicates that the turning performance is better as the numerical value is larger.

Also, tires with 1.5mm height H of each projection 10 in the first base technology (Example 5), and the height H of each projection 10 in the first base technology and 2mm tire (Example 6), tires and 2.5mm height H of each projection 10 in the first base technology (example 7), tires and 3mm height H of each projection 10 in the first base technology (example 8), first A tire (Example 9) in which the height H of each protrusion 10 is 0.5 mm was manufactured using the base technology , and the results of a similar evaluation are shown in FIG.

Further, the height H of each projection 10 in the first base technology as 2mm, the width W tire was 3.5 mm (Example 10), and 2mm height H of each projection 10 in the first base technology, the width tires and 5mm the W (example 11), the height H of each projection 10 in the first base technology and 2 mm, the tire (example 12) in which the width W and 6 mm, of each projection 10 in the first base technology A tire having a height H of 2 mm and a width W of 1.5 mm (Example 13), and a tire having a height H of each projection 10 of 2 mm and a width W of 1 mm according to the first premise technique (Example 14) FIG. 25 shows the result of manufacturing and the same evaluation.

  23, all of Examples 1 to 4 had higher snow braking performance, snow climbing performance, and circular turning performance on snow and wet road surfaces than Comparative Example 1. In addition, when the protrusions 10 adjacent to each other in the groove extending direction were different in the groove width direction, the snow braking performance, the snow climbing performance, and the circular turning performance on snow and wet road surfaces were higher.

  From FIG. 24, it was confirmed that as the height H of each protrusion 10 was increased in Example 1, the performance on snow did not change, but the circular turning performance on the wet road surface gradually decreased.

  From FIG. 25, it was confirmed that the performance on the snow did not change as the width W of each protrusion 10 in Example 6 was increased, but the circular turning performance on the wet road surface gradually decreased.

In addition, in each said premise technique and each embodiment, what provided the several protrusion 10 in the tire for ice and snow was shown, However, It is also possible to provide the protrusion 10 in an all-season tire and another type of tire, thereby It is possible to ensure smooth movement of water in the groove as described above, promote drainage from each groove, and improve performance on snow.

Moreover, in each said base technology and each embodiment, although what provided the processus | protrusion 10 in both the circumferential direction groove part 2 and the width direction groove part 3 was shown, it is also possible to provide only in any one.

In addition, in each premise technique and each embodiment, although each width direction groove part 3 showed what has continued in the tire width direction across the circumferential direction groove part 2, each width direction groove part 3 straddled the circumferential direction groove part 2 Even when they are not continuous, the same effects as described above can be obtained.

Moreover, in each premise technique and each embodiment, although each width direction groove part 3 showed what extended linearly in the width direction of a tire, each width direction groove part 3 extended in the width direction of the tire curvedly. Even in the case of being stretched while meandering, the same effect as described above can be obtained.

In each base technology and each embodiment, each circumferential groove 2 is linearly extended in the tire circumferential direction and continuous in the tire circumferential direction. However, each circumferential groove 2 is in the tire circumferential direction. Even when extending in a meandering manner or when each circumferential groove 2 extends toward the outer side in the width direction of the tire as it goes in the circumferential direction of the tire, the same effects as described above can be obtained.

  DESCRIPTION OF SYMBOLS 1 ... Tread part, 2 ... Circumferential groove part, 3 ... Width direction groove part, 4 ... Land part, 5 ... Sipe, 10 ... Protrusion, 10a ... One side curved surface part, 10b ... Other side curved surface part, 10c ... One side wall part, 10d ... the other side wall, 20 ... the projection, 20a ... one side curved surface, 20b ... the other side curved surface, 20c ... one side wall, 20d ... the other side wall, 20e ... the block, 20f ... one side facing wall, 20g ... Other side facing wall part, 30 ... projection, 30a ... one side curved surface part, 30b ... other side curved surface part, 30c ... one side wall part, 30d ... other side wall part, 30e ... hole, 40 ... projection, 40a ... one side curved surface part 40b ... the other side curved surface part, 40c ... one side wall part, 40d ... the other side wall part, 40e ... one side opposing wall part, 40f ... the other side opposing wall part, 40g ... hole, 40h ... hole, 40i ... hole, RC ... Center axis of rotation, CL: Center in the width direction.

Claims (10)

A plurality of grooves provided in the tread portion, the pneumatic tire having a plurality of lands formed on the thus tread portion to the groove portion of the plurality of,
A plurality of protrusions arranged in parallel in the extending direction of the groove in the groove,
Each projection is formed so as to protrude outward in the tire radial direction from the bottom surface of the groove portion, and is spaced apart from the side surface of the groove portion, and gradually extends from one side of the groove portion toward the other side from the groove bottom surface. One side curved surface portion of the convex curved surface that increases in height, the other curved surface portion of the convex curved surface that gradually decreases in height from the bottom surface of the groove portion from one side to the other in the direction of extending the groove portion, and the groove portion extending in the protrusion One side wall portion that is provided at the center side in the direction and forms an angle of 120 ° or less with the one side curved surface portion, and the other side curved surface portion that is provided at the center side in the groove extending direction of the projection at an angle of 120 ° or less. have a and the other side wall portion,
The groove portion has a plurality of circumferential groove portions arranged in the tire width direction and extending in the tire circumferential direction,
A plurality of protrusions arranged in a circumferential groove are formed such that the area of each protrusion when viewed from the tire radial direction is larger on the center side in the tire width direction than on the outer side in the tire width direction. the pneumatic tire according to claim that you are. In a pneumatic tire having a plurality of groove portions provided in the tread portion and a plurality of land portions formed in the tread portion by the plurality of groove portions,
A plurality of protrusions arranged in parallel in the extending direction of the groove in the groove,
Each projection is formed so as to protrude outward in the tire radial direction from the bottom surface of the groove portion, and is spaced apart from the side surface of the groove portion, and gradually extends from one side of the groove portion toward the other side from the groove bottom surface. One side curved surface portion of the convex curved surface that increases in height, the other curved surface portion of the convex curved surface that gradually decreases in height from the bottom surface of the groove portion from one side to the other in the direction of extending the groove portion, and the groove portion extending in the protrusion One side wall portion that is provided at the center side in the direction and forms an angle of 120 ° or less with the one side curved surface portion, and the other side curved surface portion that is provided at the center side in the groove extending direction of the projection at an angle of 120 ° or less. Having the other side wall,
The groove portion has a plurality of circumferential groove portions arranged in the tire width direction and extending in the tire circumferential direction,
Each protrusion provided in each circumferential groove portion is closer to the tire radial direction than each protrusion provided on the center side in the tire width direction than each protrusion in the circumferential groove portion provided on the outer side in the tire width direction. A pneumatic tire characterized by being formed to have a large area when viewed from the outside . One side in the groove part extending direction of the one side curved surface part of each projection is formed to be a convex curved surface in both the cross section along the groove part extending direction and the cross section in the direction orthogonal to the groove part extending direction,
The other side in the groove extending direction of the other curved surface portion of each protrusion is formed to be a convex curved surface in both the cross section along the groove extending direction and the cross section perpendicular to the groove extending direction. The pneumatic tire according to claim 1 or 2 , characterized by the above. Groove extending direction of spacing between the other hand side wall and the other side wall portion of the projection, according to claim 1, 2 or 3, characterized in that by comparing the height of the protrusions is three times or less Pneumatic tires. Wherein each projection is, whereas has a one side opposing wall portion facing the groove extending direction on the side wall portion, and a second side opposing wall portion facing the groove extending direction other side wall portion of the projection, each projection The interval in the groove extending direction between the one side wall portion and the one side facing wall portion is less than three times the height of the protrusion, and the groove portion extending between the other side wall portion and the other side facing wall portion in each protrusion is The pneumatic tire according to any one of claims 1 , 2 and 3 , wherein the interval in the direction is not more than three times the height of the protrusion. The range occupied by the one-side curved surface portion and the other-side curved surface portion when viewed from the tire radial direction is 50% or more of the entire projection. The pneumatic tire according to any one of the above. When the protrusion is viewed from the tire radial direction, one end of the protrusion in the groove extending direction is convex toward one of the groove extending directions, and the other end of the protrusion in the groove extending direction is in the groove extending direction. The pneumatic tire according to any one of claims 1, 2, 3, 4, 5, or 6, wherein the pneumatic tire has a convex shape toward the other side. Projections adjacent to the groove extending direction from each other, according to claim 1, 2, 3, 4, characterized in that the position in the groove width direction are arranged differently, or the seventh was 6 or Pneumatic tire described in 2. The predetermined number of protrusions adjacent to each other in the groove extending direction are arranged so that their positions are gradually shifted from one to the other in the groove width direction from one to the other in the groove extending direction. 1,2,3,4,5,6 pneumatic tire according to any one 7 or the eight. In the vulcanization mold for molding a pneumatic tire in which a plurality of groove portions and a plurality of land portions formed by the plurality of groove portions are formed in the tread portion,
Claims wherein the groove of the molded pneumatic tire 1, 2, 3, 4, so that a plurality of projections are provided according to 9 was 8 or, a recess corresponding to the projections Vulcanization mold characterized by being provided.

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