Granted Patent B2

US 12,528,315 · App. 18/040,088 · Granted Jan 20, 2026

Inventor: Takashi Kidesaki (Kanagawa, JP)

Assignee: The Yokohama Rubber Co., LTD.

B60C11/0304B60C11/1236B60C11/1263B60C11/1369B60C2011/0348B60C2011/1213B60C2011/1254

Abstract

Claims (80)

1 . A tire, comprising:

in a tread portion,

a plurality of circumferential main grooves extending in a tire circumferential direction;

a plurality of lug grooves extending in a direction intersecting the circumferential main grooves; and

a plurality of blocks defined by the circumferential main grooves and the lug grooves,

a tread surface of each of the blocks comprising a circumferential narrow groove extending in the tire circumferential direction and a plurality of sipes that are provided on both sides of the circumferential narrow groove in a tire width direction and are separated from the circumferential narrow groove, the plurality of sipes being disposed side by side in the tire circumferential direction and extending in the tire width direction,

the circumferential narrow groove comprising at least one shallow bottom portion and a deep bottom portion having different depths from the tread surface, and

the deep bottom portion having a depth from the tread surface deeper than a depth of the shallow bottom portion and being provided in a central portion of each of the blocks in the tire circumferential direction, wherein

in each of the blocks, a circumferential length L of the circumferential narrow groove and a circumferential length La of each shallow bottom portion of the at least one shallow bottom portion satisfy 0.20≤La/L≤0.35, and

a depth db of the deep bottom portion and a maximum depth dc of the sipe satisfy 0.25≤db/dc≤0.70.

2 . The tire according to claim 1 , wherein the at least one shallow bottom portion is provided at both end portions of the circumferential narrow groove.

3 . The tire according to claim 2 , wherein a depth da of the at least one shallow bottom portion, a depth db of the deep bottom portion, and a maximum depth dc of the sipe satisfy a relationship da<db≤dc.

4 . The tire according to claim 3 , wherein a depth da of the at least one shallow bottom portion and a maximum depth dc of the sipe satisfy 0.06≤da/dc≤0.30.

5 . The tire according to claim 4 , wherein, in each of the blocks, a circumferential length L of the circumferential narrow groove and a circumferential length Lb of the deep bottom portion satisfy 0.30≤Lb/L≤0.60.

6 . The tire according to claim 5 , wherein the circumferential narrow groove has a stepped groove-like shape having a bent portion between the at least one shallow bottom portion and the deep bottom portion.

7 . The tire according to claim 6 , wherein the circumferential narrow groove comprises at least one end that opens to one of the lug grooves.

8 . The tire according to claim 7 , wherein the plurality of blocks in which the circumferential narrow groove is provided are a plurality of shoulder blocks provided side by side in the tire circumferential direction on outermost sides in the tire width direction.

9 . The tire according to claim 1 , wherein a depth da of the at least one shallow bottom portion, a depth db of the deep bottom portion, and a maximum depth dc of the sipe satisfy a relationship da<db≤dc.

10 . The tire according to claim 1 , wherein a depth da of the at least one shallow bottom portion and a maximum depth dc of the sipe satisfy 0.06≤da/dc≤0.30.

11 . The tire according to claim 1 , wherein, in each of the blocks, a circumferential length L of the circumferential narrow groove and a circumferential length Lb of the deep bottom portion satisfy 0.30≤Lb/L≤0.60.

12 . The tire according to claim 1 , wherein the circumferential narrow groove has a stepped groove-like shape having a bent portion between the at least one shallow bottom portion and the deep bottom portion.

13 . The tire according to claim 1 , wherein the circumferential narrow groove comprises at least one end that opens to one of the lug grooves.

14 . The tire according to claim 1 , wherein the plurality of blocks in which the circumferential narrow groove is provided are a plurality of shoulder blocks provided side by side in the tire circumferential direction on outermost sides in the tire width direction.

15 . A tire, comprising:

in a tread portion,

a plurality of circumferential main grooves extending in a tire circumferential direction;

a plurality of lug grooves extending in a direction intersecting the circumferential main grooves; and

a plurality of blocks defined by the circumferential main grooves and the lug grooves,

a tread surface of each of the blocks comprising a circumferential narrow groove extending in the tire circumferential direction and a plurality of sipes that are provided on both sides of the circumferential narrow groove in a tire width direction and are separated from the circumferential narrow groove, the plurality of sipes being disposed side by side in the tire circumferential direction and extending in the tire width direction,

the circumferential narrow groove comprising at least one shallow bottom portion and a deep bottom portion having different depths from the tread surface, and

the deep bottom portion having a depth from the tread surface deeper than a depth of the shallow bottom portion and being provided in a central portion of each of the blocks in the tire circumferential direction, wherein

the circumferential narrow groove comprises only one end that opens to one of the lug grooves,

in each of the blocks, a circumferential length L of the circumferential narrow groove and a circumferential length La of each shallow bottom portion of the at least one shallow bottom portion satisfy 0.20≤La/L≤0.35, and

a depth db of the deep bottom portion and a maximum depth de of the sipe satisfy 0.25≤db/dc≤0.70.

16 . A tire, comprising:

in a tread portion,

a plurality of circumferential main grooves extending in a tire circumferential direction;

a plurality of lug grooves extending in a direction intersecting the circumferential main grooves; and

a plurality of blocks defined by the circumferential main grooves and the lug grooves,

a tread surface of each of the blocks comprising a circumferential narrow groove extending in the tire circumferential direction and a plurality of sipes that are provided on both sides of the circumferential narrow groove in a tire width direction and are separated from the circumferential narrow groove, the plurality of sipes being disposed side by side in the tire circumferential direction and extending in the tire width direction,

the circumferential narrow groove comprising a shallow bottom portion and a deep bottom portion having different depths from the tread surface, and

the deep bottom portion having a depth from the tread surface deeper than a depth of the shallow bottom portion and being provided in a central portion of each of the blocks in the tire circumferential direction, wherein

in each of the blocks, a circumferential length L of the circumferential narrow groove and a circumferential length La of the shallow bottom portion satisfy 0.20≤La/L≤0.35,

a depth db of the deep bottom portion and a maximum depth dc of the sipe satisfy 0.25≤db/dc≤0.70,

the shallow bottom portion is provided at both end portions of the circumferential narrow groove, and

only a single of the deep bottom portions is provided between the shallow bottom portions.

17 . A tire, comprising:

in a tread portion,

a plurality of circumferential main grooves extending in a tire circumferential direction;

a plurality of lug grooves extending in a direction intersecting the circumferential main grooves; and

a plurality of blocks defined by the circumferential main grooves and the lug grooves,

a tread surface of each of the blocks comprising a circumferential narrow groove extending in the tire circumferential direction and a plurality of sipes that are provided on both sides of the circumferential narrow groove in a tire width direction and are separated from the circumferential narrow groove, the plurality of sipes being disposed side by side in the tire circumferential direction and extending in the tire width direction,

the circumferential narrow groove comprising a shallow bottom portion and a deep bottom portion having different depths from the tread surface, and

the deep bottom portion having a depth from the tread surface deeper than a depth of the shallow bottom portion and being provided in a central portion of each of the blocks in the tire circumferential direction, wherein

the circumferential narrow groove comprises only one end that opens to one of the lug grooves,

a depth db of the deep bottom portion and a maximum depth dc of the sipe satisfy 0.25≤db/dc≤0.70,

the shallow bottom portion is provided at both end portions of the circumferential narrow groove, and

only a single of the deep bottom portions is provided between the shallow bottom portions.

18 . A tire, comprising:

in a tread portion,

a plurality of circumferential main grooves extending in a tire circumferential direction;

a plurality of lug grooves extending in a direction intersecting the circumferential main grooves; and

a plurality of blocks defined by the circumferential main grooves and the lug grooves,

a tread surface of each of the blocks comprising a circumferential narrow groove extending in the tire circumferential direction and a plurality of sipes that are provided on both sides of the circumferential narrow groove in a tire width direction and are separated from the circumferential narrow groove, the plurality of sipes being disposed side by side in the tire circumferential direction and extending in the tire width direction,

the circumferential narrow groove comprising a shallow bottom portion and a deep bottom portion having different depths from the tread surface, and

the deep bottom portion having a depth from the tread surface deeper than a depth of the shallow bottom portion and being provided in a central portion of each of the blocks in the tire circumferential direction, wherein

in each of the blocks, a circumferential length L of the circumferential narrow groove and a circumferential length La of the shallow bottom portion satisfy 0.20≤La/L≤0.35,

a depth db of the deep bottom portion and a maximum depth dc of the sipe satisfy 0.25≤db/dc≤0.70, and

in each of the blocks, a circumferential length L of the circumferential narrow groove and a circumferential length Lb of only a single of the deep bottom portions satisfy 0.30≤Lb/L≤0.60.

19 . A tire, comprising:

in a tread portion,

a plurality of circumferential main grooves extending in a tire circumferential direction;

a plurality of lug grooves extending in a direction intersecting the circumferential main grooves; and

a plurality of blocks defined by the circumferential main grooves and the lug grooves,

a tread surface of each of the blocks comprising a circumferential narrow groove extending in the tire circumferential direction and a plurality of sipes that are provided on both sides of the circumferential narrow groove in a tire width direction and are separated from the circumferential narrow groove, the plurality of sipes being disposed side by side in the tire circumferential direction and extending in the tire width direction,

the circumferential narrow groove comprising a shallow bottom portion and a deep bottom portion having different depths from the tread surface, and

the deep bottom portion having a depth from the tread surface deeper than a depth of the shallow bottom portion and being provided in a central portion of each of the blocks in the tire circumferential direction, wherein

the circumferential narrow groove comprises only one end that opens to one of the lug grooves,

a depth db of the deep bottom portion and a maximum depth dc of the sipe satisfy 0.25≤db/dc≤0.70, and

in each of the blocks, a circumferential length L of the circumferential narrow groove and a circumferential length Lb of only a single of the deep bottom portions satisfy 0.30≤Lb/L≤0.60.

Assignments (2)

Priority Claims (1)

Continuity (1)

References Cited (17)