tire

Abstract

To achieve both performance on ice and snow and wear resistance. [Solution] The center portion land portion 30 includes center portion blocks 311, 321 that are separated by a center portion lug groove 50 having a bent portion in the middle and arranged in a staggered pattern via a circumferential main groove 20, the shoulder portion land portion 33 includes a shoulder portion inner block 33A1 that is separated by a zigzag-shaped circumferential narrow groove 40 and a shoulder portion inner lug groove 61, the shoulder portion land portion 33 includes a shoulder portion outer block 33B1 that is separated by a circumferential narrow groove 40 and a shoulder portion outer lug groove 62 and arranged in a staggered pattern with the shoulder portion inner block 33A1 via the circumferential narrow groove 40, open sipes 71 that are placed on each center portion block 311, 321, and closed sipes 81 that are placed on each shoulder portion inner block 33A1 and each shoulder portion outer block 33B1.

Claims

1. In the tread portion, a center portion is formed by circumferential main grooves that extend along the circumferential direction of the tire and meander in the tire width direction, with at least four such grooves arranged in the tire width direction, and the center portion is divided into multiple sections between each of the outermost circumferential main grooves in the tire width direction, and the shoulder portion is divided into sections on the outside in the tire width direction of each of the outermost circumferential main grooves in the tire width direction, In each of the aforementioned center portions, a center portion block extends along the tire width direction, has a bend in the middle, and both ends open into the circumferential main groove, is partitioned by a plurality of center portion lug grooves arranged in the circumferential direction of the tire, and is arranged in a staggered pattern via the circumferential main groove, In the shoulder portion of the land area, there is a circumferential narrow groove that is narrower in width than the circumferential main groove, extends along the tire circumferential direction, and is bent in the tire width direction to have a zigzag shape, and a shoulder portion inner block that is partitioned by multiple shoulder portion inner lug grooves arranged in the tire circumferential direction, with one end opening into the outermost circumferential main groove in the tire width direction and the other end opening into the circumferential narrow groove. In the shoulder portion land area, the shoulder portion outer blocks are separated by the circumferential grooves and the shoulder portion outer lug grooves, one end of which opens into the circumferential grooves and the other end of which opens to the ground contact end, and which are arranged in a staggered pattern with respect to the shoulder portion inner blocks via the circumferential grooves. Each of the center blocks includes an open sipe that extends along the tire width direction and has at least one end opening into the circumferential main groove, Each of the shoulder portion inner block and each of the shoulder portion outer block is provided with a closed sipe that extends along the tire width direction and is closed at both ends, Tires, including.

2. In the circumferential main groove, the groove width W1 and the maximum dimension A1 in the meandering tire width direction between the opening end forming the groove width W1 satisfy the relationship 1.00 < A1 / W1 < 1.

50. The tire according to claim 1.

3. The maximum dimension A2 in the tire width direction of the zigzag shape in the circumferential narrow groove and the maximum dimension A1 in the tire width direction of the meandering section between the opening ends forming the groove width W1 in the circumferential main groove satisfy the relationship A2 < A1. The tire according to claim 1.

4. The aforementioned circumferential grooves have a zigzag shape that straddles the center line in the tire width direction of the shoulder portion of the land area. The tire according to claim 1.

5. The center lug groove has a narrower groove width than the circumferential main groove, and the straight line connecting both ends is inclined by more than ±5° with respect to the tire width direction, and the inclination direction differs in each adjacent center land portion in the tire width direction, with respect to the circumferential main groove. The tire according to claim 1.

6. The center lug groove has two bends, the center line in the tire width direction of the center land portion is positioned between each bend, and the relationship between the center line and the bends on both sides in the tire width direction is within ±5%. The tire according to claim 1.

7. In each of the adjacent center blocks in the tire circumferential direction, separated by the center lug groove, both edge portions that form the opening end of the groove width of the center lug groove are inclined beyond ±5° with respect to the tire width direction. In each of the adjacent inner shoulder blocks in the tire circumferential direction, separated by the inner shoulder lug groove, the angle of both edges that form the opening end of the groove width of the inner shoulder lug groove with respect to the tire width direction is within ±5°. In each of the adjacent outer blocks of the shoulder portion in the tire circumferential direction, separated by the outer lug groove of the shoulder portion, the angle of both edges that form the opening end of the groove width of the outer lug groove of the shoulder portion with respect to the tire width direction is within ±5°. The tire according to claim 1.

8. In each of the center blocks adjacent to each other in the tire circumferential direction with respect to the center lug groove, the angle of both edges that form the opening end of the groove width of the center lug groove with respect to the tire width direction and the angle of the open sipe with respect to the tire width direction are within ±5°. In each of the adjacent inner shoulder blocks in the tire circumferential direction, separated by the inner shoulder lug groove, the angle of both edges that form the opening end of the groove width of the inner shoulder lug groove with respect to the tire width direction and the angle of the closed sipe with respect to the tire width direction are within ±5°. In each of the shoulder outer blocks adjacent to each other in the tire circumferential direction with respect to the shoulder outer lug groove, the angle of both edges that form the opening end of the groove width of the shoulder outer lug groove with respect to the tire width direction and the angle of the closed sipe with respect to the tire width direction are within ±5°. The tire according to claim 1.

9. The groove depth D1 of the circumferential main groove, the groove depth D2 of the center lug groove, the groove depth D3 of the circumferential narrow groove, and the groove depth D4 of the inner lug groove and outer lug groove of the shoulder portion satisfy the relationship D3 ≤ D4 < D2 < D1. The tire according to claim 1.

10. The groove depths D4 of the inner lug groove of the shoulder portion and the outer lug groove of the shoulder portion, the groove depth D5 of the open sipe, and the groove depth D6 of the closed sipe satisfy the relationship D6 ≤ D5 ≤ D4. The tire according to claim 1.

11. The number of open sipes arranged in one center block is less than the number of closed sipes arranged in one inner shoulder block or one outer shoulder block. The tire according to claim 1.

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