JP6722028B2 - tire - Google Patents

Description

The present invention relates to a winter tire that travels on snow, and more particularly to the shape of a buttress portion that can improve snow running performance.

Conventionally, as a tread pattern for winter tires, in order to improve running performance on snow, a sipe is formed on the surface of a block divided by a lug groove extending in a direction intersecting the circumferential groove and the circumferential groove and the lug groove. In addition, a stepless auxiliary land portion extending in the tire circumferential direction is formed in the buttress portion (see, for example, Patent Document 1).
In Patent Document 1, further, the contact area between the snow and the shoulder block in the snow is increased by making the tire radial outer surface portion of the stair-shaped auxiliary land portion into a zigzag shape, thereby increasing the braking performance and the traction performance. Is said to be able to improve.

JP, 2003-213915, A

In the tire of the above Patent Document 1, the snow running performance was exhibited by the edge effect of the ridge line of the corner of the block of the lug groove and the snow column shearing force by the recess of the lug groove, but in the buttress portion, other than the recess of the lug groove. Has a problem that it is difficult to obtain sufficient running performance on snow because it does not contribute to the shear force of the snow column.

The present invention has been made in view of the conventional problems, and an object of the present invention is to provide a tire having a buttress portion capable of improving the running performance on snow.

The present invention is a tire including a lug groove intersecting in the circumferential direction of the tire and a land portion partitioned by the lug groove, and a tire radial direction maximum of a sidewall portion from a ground contact end of a tread portion of the tire. On the surface of the buttress portion extending to the outer end, a plurality of concave portions formed at predetermined intervals in the tire circumferential direction and extending over two land portions adjacent to each other in the tire circumferential direction with the lug groove interposed are formed. The tread portion is formed on the ground contact end side of the tread portion, and the tread portion is closer to the sidewall portion side than the tread portion side recess, and more than the groove bottom of the lug groove. possess a side-side recess formed in the ground terminal side parts, the bottom surface of the tread side recess parallel to the surface of the buttress portion, and side surfaces and wherein the planar der Rusuru.
The concave portion according to the present invention includes a step side concave portion which is opened to the step side of the lug groove and extends toward the land portion side of the step side, and a kick side concave portion which is opened to the kick side and extends toward the land portion side of the kick side. Therefore, when the snow enters the lug groove, the tread side recess functions as an entrance of the funnel to the lug groove, so it is easy for the snow to enter, and when the snow comes out from the lug groove, the kick side recess is hardened. Since the snow is guided to the kicking side, the snow column shearing force of the lug groove can be increased, and the running performance on snow can be improved.
Further, by forming the recesses at a predetermined interval in the tire circumferential direction, the corners of the ridgeline that is the boundary line between the recesses and the land surface can scratch the snow near the lug grooves. The edge effect is increased.
Further, since the bottom surface of the tread-side concave portion is formed so as to be parallel to the surface of the buttress portion and the side surface thereof is flat, it is possible to increase the amount of snow taken into the concave portion. Power can be further enhanced.

Further, in the present invention, the extension direction of the side-side concave portion when the surface of the buttress portion is viewed from the tire tread side, the end on the stepping side is located outside the end on the kicking side in the tire width direction. It is characterized in that it is inclined with respect to the tire circumferential direction.
As a result, even in the side recess, the end on the tread side can be located farther from the tread, and the end on the kicking side can be located closer to the tread, so that the snow will fall from the tread to the tread. Can be carried to the near side. Therefore, since snow can be effectively guided to the lug groove, the snow column shearing force of the lug groove can be further increased, and the running performance on snow is further improved.
Further, by making the cross-sectional shape of the side concave portion cut along a plane perpendicular to the tire circumferential direction into an arc shape, it is possible to secure the rigidity of the land portion around the side concave portion. Since snow coming out of the rug groove by the land portion and snow that does not enter the rug groove can be compacted, the snow column shearing force of the rug groove can be further increased.

In the present invention, the side-side recess is provided on the kick-out side, and the kick-out side communicating portion communicating with the side-side recess located on the kick-out side of the side-side recess is provided on the step-in side. And a depression-side communication portion that communicates with the groove bottom side of the lug groove, and communicates with the tread-side recess on the kicking side.
As a result, the lug groove on the stepping side and the lug groove on the kicking side communicate with each other through the side-side concave portion and the tread-side concave portion, so that snow can be easily carried from the side far from the tread to the side close to the tread. .. Therefore, the snow column shearing force of the lug groove can be further increased, and the running performance on snow can be further improved.

The above summary of the invention does not enumerate all the necessary features of the present invention, and sub-combinations of these feature groups can also be the invention.

It is a figure which shows the tread pattern of the tire which concerns on this Embodiment. It is an enlarged view of a buttress portion. It is a perspective view and a partially enlarged view of a buttress portion.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing an example of a development view of a tread portion 11 of a tire 10 according to the present embodiment, FIG. 2 is an enlarged view of a buttress portion 12, and FIGS. 3(a) and 3(b) are perspective views of the buttress portion 12. It is a figure and a partially enlarged view.
The direction from the upper side to the lower side in FIG. 1 is the tire rotation direction, the upper side in the figure is the kicking side, and the lower side is the stepping side. Further, the left-right direction in the figure is the tire width direction, CL is the tire equatorial plane, and TG is the end portion in the tire width direction of the tire tread surface where the tread portion 11 is in contact with the ground (hereinafter referred to as the tread ground contact end). ..
Hereinafter, the tire equatorial plane CL side along the tire width direction is referred to as “tire width direction inner side”, and the side opposite to the tire equatorial plane CL is referred to as “tire width direction outer side”.
Further, a region extending from the tread grounding end TG to a tread end which is an end of the tread part 10 shown by TE in FIG. 1 is called a buttress part 12. The tread edge TE is the outermost edge of the sidewall portion 13 in the tire radial direction, as shown in FIG.

A plurality of lug grooves 14 and sub-grooves 15 are provided on the surface of the tread portion 11 at predetermined intervals in the tire circumferential direction. The lug groove 14 and the sub groove 15 partition the center land portion 16 located in the tread center portion 11C and the shoulder land portion 17 located in the shoulder portion 11S. A plurality of sipes 18 extending in a direction parallel to the tire width direction are formed on the surfaces of the center land portion 16 and the shoulder land portion 17.
The sipes 18 may be linear sipes as shown in FIG. 1 or zigzag sipes (2D sipes) as shown in FIGS. 3(a) and 3(b). Also, the sipe 18 may be a 3D sipe.
The lug groove 14 is a groove that extends obliquely in the tire width direction from the tread center portion 11C to the side opposite to the tire rotation direction and opens at the tread end T E. It is divided into the land portion (buttress land portion 19).
As shown in FIG. 2, a plurality of recesses 21 and 22 are formed on the surface of the buttress portion 12 so as to extend over two adjacent buttress land portions 19 with the lug groove 14 interposed therebetween. Both the tread-side concave portion 21 and the side-side concave portion 22 are formed at a predetermined interval in the tire circumferential direction.
The concave portion formed on the end side of the tread portion 11 is referred to as a tread-side concave portion 21, and the concave portion formed closer to the sidewall portion 13 side than the tread-side concave portion 21 is referred to as a side-side concave portion 22.
The tread-side concave portion 21 opens to the tread end TE, the tread-side end ends in the tread-side buttress land portion (the tread-side land portion 19F), and the kick-out side end is the kick-out-side land. Ends in the section (kick side land portion 19K) and opens from the tread side land portion 19F and the kick side land portion 19K to the lug groove 14M that divides the tread side land portion 19F and the kick side land portion 19K. ..
Further, the side-side recessed portion 22 has an end on the stepping side that ends within the landing portion 19F on the stepping side, an end on the kicking side that ends within the landing portion 19K on the kicking side, and a kicking off with the landing portion 19F on the stepping side. It opens from the side land portion 19K to the lug groove 14M that divides the tread side land portion 19F and the kick side land portion 19K.
When the buttress land portion 19A on the stepping side of the tread side land portion 19F is used as the tread side land portion, the tread side land portion 19F becomes the kick side land portion, and the buttress land on the kick side of the kick side land portion 19K. It goes without saying that when the portion 19B is the kick-side land portion, the kick-side land portion 19K is the step-side land portion.

The tread-side concave portion 21 is a groove having a trapezoidal shape when viewed from the tire tread side, and is opened on the tread-side land portion of the lug groove 14M that divides the tread-side land portion 19F and the kick-side land portion 19K. The depression side recess 21F extends to the 19F side and ends, and the kick side recess 21K opens to the kick side of the lug groove 14M and extends to the land side on the kick side to end.
A side 21a of the tread-side concave portion 21 on the tread ground contact end TG side is parallel to the tire circumferential direction, and a side 21b of the sidewall portion, which is a side facing the side 21a, has an end on the stepping side on the kicking side. The tire is inclined with respect to the tire circumferential direction so as to be located outside the portion in the tire width direction. Further, two mutually parallel sides 21c and 21d of the trapezoid are inclined with respect to the tire circumferential direction so as to be located on the stepping side as they go outward in the tire width direction.
Therefore, when snow enters the lug groove 14M, the step-side concave portion 21F functions as an inlet of the funnel with respect to the lug groove 14M, so that snow easily enters. Further, when the snow comes out from the lug groove 14M, the kick-side recess 21K functions to guide the hardened snow to the kick-out side. Therefore, the snow column shearing force of the lug groove 14M can be increased, and the running performance on snow can be improved.
Further, since the tread side concave portion 21 of the present example is opened at the tread end TE, it is easy to scrape snow and sweep it out. Therefore, it is easy to put snow from the inside (lower side) on the tread.
Further, since the tread-side recesses 21 are formed at a predetermined interval in the tire circumferential direction, the surface of the buttress land portion 19 is between adjacent tread-side recesses 21. The surface of the buttress land portion 19 which is a protrusion with respect to the kick-side recess 21K is referred to as a protrusion 23a for convenience. As described above, the presence of the protrusions 23a between the tread-side recesses 21 prevents the snow hardened in the lug grooves 14 from freely exiting, so that the tread-side recesses 21 do not terminate in the buttress land portion 19. Compared to the case, the snow column shearing force of the lug groove 14 is improved.
Further, since the edge effect of the trapezoidal ridge lines (the upper bottom 21c and the lower bottom 21d) intersecting in the tire circumferential direction can be obtained, the snow running performance can be improved.
Further, as shown in FIGS. 3A and 3B, the tread-side concave portion 21 is formed such that the bottom surface is parallel to the surface of the buttress portion 12 and the side surface is flat. This is because, when the cross-sectional shape of the tread-side recess 21 is an outer radius R such as an arc shape, the amount of snow taken into the tread-side recess 21 decreases, so the amount of snow induced in the lug groove 14 decreases. Is. Further, since the tread-side concave portion 21 is close to the tire tread, if the inside R is set to R, the volume of the buttress land portion 19 may decrease and the land rigidity may decrease.

The side-side concave portion 22 is a groove that is formed on the sidewall portion 13 side of the tread-side concave portion 21 and on the tread end TE side of the groove bottom of the lug groove 14 at a predetermined interval in the tire circumferential direction. The extension direction when viewed from the tire tread surface side is formed so that the end portion on the stepping side in the tire rotation direction is located outside the end portion on the kicking side in the tire width direction.
The side-side concave portion 22 has a parallelogram-shaped main concave portion 22M when viewed from the tire tread side, a kick-side communication portion 22p provided on the kick-out side of the main concave portion 22M, and a step-in side of the main concave portion 22M. The provided tread side communication portion 22q is provided.
The main concave portion 22M is a tread main concave portion 22F which opens to the step side of the lug groove 14M which divides the land portion 19F on the stepping side and the land portion 19K on the kick side, and which extends to the side of the land portion 19F on the tread side and terminates. The groove 14M includes a kick-side main recessed portion 22K which is open to the kick-out side and extends toward the land side on the kick-out side to end.
The kick-out side communicating portion 22p is a parallelogrammatic recess in plan view provided at the kick-out side end of the kick-side main recess 22K. The kick-side main recess 22K of the side recess 22 and the tread-side recess 21 The kick-side concave portion 21F communicates with the step-side communication portion 22q of the side-side concave portion 22 on the kick-out side of the side-side concave portion 22.
The step-side communication portion 22q is a parallelogrammatic concave section provided in the step-side end of the step-side main concave portion 22F, and includes the step-side main concave portion 22F of the side-side concave portion 22 and the side-side concave portion. It connects with the lug groove 14A and the step-side communication portion 22q of the side-side concave portion 22 located on the step-in side of 22.
In this example, in the extending direction of the side of the kick-out side communicating portion 22p on the kick-out end side, the kick-out side communicating portion 22q of the side-side concave portion 22A on the kick-out side of the side-side concave portion 22 is kicked out. The side on the end side is positioned, and the step side communication portion 22q of the side recess 22A on the kick side of the side recess 22 is depressed in the extension direction of the side of the step end of the kick side communication portion 22p. By arranging the side on the end side, the side-side recesses 22 in the buttress land portion 19 are arranged in the same manner.

The tread side main recessed portion 22F has one end opening to the lug groove 14M and the other end through the tread side communication portion 22q through the tread side lug groove 14A on the tread side of the lug groove 14M. Since it is opened inward in the radial direction, it functions to guide the snow hardened in the lug groove 14A to the lug groove 14M on the kicking side. Therefore, the snow generated from the lug groove 14A can be smoothly guided to the lug groove 14M.
On the other hand, the kick-side main concave portion 22K of the main concave portion 22M has one end opening to the lug groove 14M and the other end terminating at the kick-side land portion 19K, so when snow comes out of the lug groove 14M, Since the side main recessed portion 22K functions to guide the hardened snow to the kicking side, the snow column shearing force of the lug groove 14M can be increased and the snow running performance can be improved.
As described above, even in the side-side concave portion 22, the end on the stepping side is located farther from the tread, and the end on the kicking side is located closer to the tread, so that snow falls from the tread to the tread. Can be carried to the near side. Therefore, since snow can be effectively guided to the lug groove, the snow column shearing force of the lug groove can be further increased, and the running performance on snow is further improved.

Further, since the side recesses 22 are also formed at a predetermined interval in the tire circumferential direction, the land portion 19 exists between the adjacent side recesses 22. This land portion 19 becomes a convex portion 23b with respect to the kick-side main concave portion 22K, and the snow hardened in the lug groove 14 cannot come out without permission, so the side-side concave portion 22 ends at the buttress land portion 19. The snow column shear force of the lug groove 14M is improved as compared with the case where it is not performed.
Further, since the tread side main concave portion 22F ends in the buttress land portion 19, the land portion between the tread side main concave portion 22F and the lug groove 14A is a convex portion 23c with respect to the tread side main concave portion 22F. Therefore, the snow in the lug groove 14A can be effectively hardened.
Further, since the edge effect is obtained by the ridge lines (upper side 22a and lower side 22b) formed on both sides of the main recessed portion 22M in the tire circumferential direction, it is possible to improve the snow running performance.

The side recess 22 has an arc-shaped cross section when cut along a plane perpendicular to the tire circumferential direction. This is because the side-side recess 22 is farther from the tire tread side than the tread-side recess 21, so that the rigidity of the land portion around the side-side recess 22 shown by reference numerals 23a to 23d is larger than the amount of snow taken in. This is because priority was given to securing As a result, snow that comes out of the lug groove due to the land portion and snow that does not enter the lug groove can be compacted, so that the snow column shearing force of the lug groove can be further increased.

Although the present invention has been described above using the embodiment, the technical scope of the present invention is not limited to the scope described in the above embodiment. It is apparent to those skilled in the art that various modifications and improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

For example, in the above-described embodiment, the tread-side recess 21 has a trapezoidal shape, but may have a triangular shape. In this case as well, the side of the triangular tread ground contact end TG side is parallel to the tire circumferential direction, and the other two sides are positioned so that the end on the stepping side is located outside the end on the kicking side in the tire width direction. It is preferable to incline with respect to the tire circumferential direction.
As a result, the edge effect on the kicking side (bottom side) can be obtained, so that it is possible to improve the running performance on snow, and the end on the stepping side is far from the tread and the end on the kicking side is Since it is on the side closer to the tread, snow can be effectively guided to the lug groove, and the snow column shearing force of the lug groove 14 can be further increased.
As described above, the cross-sectional shape of the tread-side recess 21 and the cross-sectional shape of the side-side recess 22 are not limited to rectangles or arcs, and may be determined in consideration of the amount of snow to be taken into the recess and the rigidity of the land. ..

10 tires, 11 tread parts, 11C tread center parts,
12 buttress portion, 13 sidewall portion, 14 lug groove, 15 sub groove,
16 center land area, 17 shoulder land area, 18 sipes,
19 Buttress land part, 19F Tread side land part, 19K Kick side land part,
21 tread side concave portion, 22 side concave portion,
CL tire equatorial plane, TG tread ground contact edge, TE tread edge.

Claims (4)

A tire having a lug groove intersecting in the circumferential direction of the tire and a land portion partitioned by the lug groove,
On the surface of the buttress portion extending from the ground contact end of the tread portion of the tire to the outermost end in the tire radial direction of the sidewall portion, the lug groove formed at a predetermined interval in the tire circumferential direction is sandwiched. A plurality of recesses are formed across two adjacent land areas.
The plurality of recesses,
A tread side concave portion formed on the grounding end side of the tread portion,
In the side wall portion side of the tread surface side recess, and than the groove bottom of the lug groove possess a side-side recess formed in the ground terminal side of the tread portion,
Parallel to the surface of the bottom buttress portion of the tread surface side recess, and tire side surface and said planar der Rukoto. The extension direction of the side concave portion when the surface of the buttress portion is viewed from the tire tread side is in the tire circumferential direction so that the end on the stepping side is located outside the end on the kicking side in the tire width direction. The tire according to claim 1, wherein the tire is inclined with respect to the tire. The tire according to claim 1 or 2, wherein a cross-sectional shape of the side-side concave portion taken along a plane perpendicular to the tire circumferential direction is an arc shape. The side-side recess is
The kick-out side communication portion provided on the kick-out side and communicating with the side-side concave portion located on the kick-out side of the side-side concave portion, and the step-in side provided on the depression side and communicating with the groove bottom side of the lug groove With a communication part,
The tire according to any one of claims 1 to 3 , which communicates with the tread-side recess on the kicking side.

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