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US 11,951,772 B2Granted
Pneumatic tire
AssigneeThe Yokohama Rubber Co., Ltd.
InventorMasatoshi Shimizu
Life of this patent
Estimating the term…
Abstract
In a pneumatic tire, a tread portion includes a main groove extending in a circumferential direction, and land portions defined by the main groove. A center region is a region where a center land portion included in the land portions is closest to a tire equatorial plane. Shoulder regions are each a region between a position corresponding to 85% of a width of the belt layer in a lateral direction and an end portion of the belt layer in the lateral direction, and intermediate regions are each a region between the center region and a corresponding one of the shoulder regions. A relationship among a tire average thickness Gc in the center region, a tire average thickness Gsh in the shoulder regions, and a tire average thickness Gm in the intermediate regions is within a range of 1.05≤(Gc/Gsh)≤1.35 and satisfies Gc≥Gm>Gsh.
Claims18
A pneumatic tire comprising:
- at least one carcass layer;
- a belt layer disposed outward, in a tire radial direction, of a portion of the carcass layer located in a tread portion;
- and
- a tread rubber layer disposed outward, in the tire radial direction, of the belt layer in the tread portion,
- the tread portion being provided with a main groove extending in a tire circumferential direction, and a plurality of land portions defined by the main groove, and
- in the tread portion,
- assuming that a center region is a region where a center land portion included in the land portions and corresponding to the land portion closest to a tire equatorial plane is located,
- shoulder regions are each a region between a position corresponding to 85% of a width of the belt layer in a tire lateral direction and an end portion of the belt layer in the tire lateral direction, and
- intermediate regions are each a region between the center region and a corresponding one of the shoulder regions,
- a relationship between a tire average thickness Gc in the center region and a tire average thickness Gsh in the shoulder regions and a tire average thickness Gm in the intermediate regions being within a range of 1.05≤(Gc/Gsh)≤1.35 and satisfying a relationship Gc≥Gm>Gsh, and
- in the tread portion, a relationship between an average actual rubber thickness Vc of the tread rubber layer in the center region and an average actual rubber thickness Vsh of the tread rubber layer in the shoulder regions is within a range of 1.7≤(Vc/Vsh)≤2.5;
- wherein
- at least one of the land portions located in the center region or the intermediate regions is formed as a projection-shaped land portion, and
- the projection-shaped land portion of the at least one of the land portions located in the center region or the intermediate regions is formed on fewer than all of the land portions located in the center region and the intermediate regions and is formed in an arc shape in which a ground contact surface representing an outer contour line in a tire meridian cross-sectional view bulges outward in the tire radial direction, and a relationship between a radius of curvature RR of the arc and a radius of curvature TR of an arc forming a tread profile is within a range of 0.1≤(RR/TR)≤0.25.
11 more elements
A pneumatic tire comprising:
- at least one carcass layer;
- a belt layer disposed outward, in a tire radial direction, of a portion of the carcass layer located in a tread portion;
- and
- a tread rubber layer disposed outward, in the tire radial direction, of the belt layer in the tread portion,
- the tread portion being provided with a main groove extending in a tire circumferential direction, and a plurality of land portions defined by the main groove, and
- in the tread portion,
- assuming that a center region is a region where a center land portion included in the land portions and corresponding to the land portion closest to a tire equatorial plane is located,
- shoulder regions are each a region between a position corresponding to 85% of a width of the belt layer in a tire lateral direction and an end portion of the belt layer in the tire lateral direction, and
- intermediate regions are each a region between the center region and a corresponding one of the shoulder regions,
- a relationship between a tire average thickness Gc in the center region and a tire average thickness Gsh in the shoulder regions and a tire average thickness Gm in the intermediate regions being within a range of 1.05≤(Gc/Gsh)≤1.35 and satisfying a relationship Gc≥Gm>Gsh, and
- in the tread portion, a relationship between an average actual rubber thickness Vc of the tread rubber layer in the center region and an average actual rubber thickness Vsh of the tread rubber layer in the shoulder regions is within a range of 1.7≤(Vc/Vsh)≤2.5;
- wherein
- a portion of rubber forming the tread rubber layer that is contained in the center region is 12 MPa or more and 16 MPa or less in modulus of 300% elongation, and
- in the tread portion, a relationship between an average thickness Tc of the tread rubber layer located outward, in the tire radial direction, from the belt layer in the center region, and an average thickness Tsh of the tread rubber layer located outward, in the tire radial direction, from the belt layer in the shoulder regions is within a range of 1.7≤(Tc/Tsh)≤1.9.
11 more elements
Dependencies are inferred from the claim text.