Pneumatic radial tire having buttress

1. A pneumatic radial tire having a thin groove continuous in a tire circumferential direction at a buttress formed between a shoulder of a tread and a sidewall, comprising:

a tire contour portion that is formed between an end portion of the shoulder and a groove floor of the thin groove, and

at least one circumferential direction groove, wherein the groove floor of the thin groove is positioned radially inwardly of a groove floor of the at least one circumferential direction groove;

wherein a tire transverse direction outermost portion at a shoulder side curved portion is disposed further toward a tire radial direction inner side than a sidewall side end portion of a sidewall side groove wall surface of the thin groove, such that the tire transverse direction outermost portion and the sidewall side end portion are located in the same radial plane perpendicular to the axis of rotation of the tire,

wherein the tire contour portion includes an inclined portion from the end portion of the shoulder toward the thin groove and a shoulder side groove wall surface of the thin groove,

wherein the tire transverse direction outermost portion is an intersection of the inclined portion and the shoulder side groove wall surface at the shoulder side curved portion,

wherein the end portion of the shoulder is closer to a width center of the tire in a width direction than the entire thin groove,

wherein said sidewall side end portion of the sidewall side groove wall surface of the thin groove is radially inside said end portion of said shoulder,

wherein the sidewall side groove wall surface of the thin groove is formed further to a tire radial direction outer side than the shoulder side curved portion of the tire contour portion, and includes a sidewall side curved portion at a position facing the shoulder side curved portion of the tire contour portion, and

wherein said sidewall side end portion of the sidewall side groove wall surface of the thin groove contacts said inclined portion when the buttress is deformed by a lateral force.

2. The pneumatic radial tire according to claim 1 , wherein the sidewall side groove wall surface of the thin groove is formed parallel to the tire contour portion.

3. The pneumatic radial tire according to claim 1 , wherein the thin groove extends from the groove floor in an outward direction with respect to both a tire radial direction and a tire width direction, and opens outwardly in a meridional cross-section.

4. A pneumatic radial tire having a thin groove continuous in a tire circumferential direction at a buttress formed between a shoulder of a tread and a sidewall, comprising:

a tire contour portion that is formed between an end portion of the shoulder and a groove floor of the thin groove, and

at least one circumferential direction groove, wherein the groove floor of the thin groove is positioned radially inwardly of a groove floor of the at least one circumferential direction groove;

wherein a tire transverse direction outermost portion at a shoulder side curved portion is disposed further toward a tire radial direction inner side than a sidewall side end portion of a sidewall side groove wall surface of the thin groove, such that the tire transverse direction outermost portion and the sidewall side end portion are located in the same radial plane perpendicular to the axis of rotation of the tire,

wherein a difference between a first tire radial direction distance from a tire radial direction outermost portion of the tread to the tire transverse direction outermost portion and a second tire radial direction distance from the tire radial direction outermost portion of the tread to the sidewall side end portion is in a range between 2 millimeters and 10 millimeters, and

wherein the end portion of the shoulder is closer to a width center of the tire in a width direction than the entire thin groove,

wherein said sidewall side end portion of the sidewall side groove wall surface of the thin groove is radially inside said end portion of said shoulder,

wherein the sidewall side groove wall surface of the thin groove is formed further to a tire radial direction outer side than the shoulder side curved portion of the tire contour portion, and includes a sidewall side curved portion at a position facing the shoulder side curved portion of the tire contour portion, and

wherein said sidewall side end portion of the sidewall side groove wall surface of the thin groove contacts an inclined portion of the tire contour portion when the buttress is deformed by a lateral force.

5. The pneumatic radial tire according to claim 4 , wherein the sidewall side groove wall surface of the thin groove is formed parallel to the tire contour portion.

6. The pneumatic radial tire according to claim 4 , wherein the thin groove extends from the groove floor in an outward direction with respect to both a tire radial direction and a tire width direction, and opens outwardly in a meridional cross-section.

7. A pneumatic radial tire comprising:

a buttress between a shoulder of a tread and a sidewall, a thin groove extending into said buttress to a groove floor, and

at least one circumferential direction groove, wherein the groove floor of the thin groove is positioned radially inwardly of a groove floor of the at least one circumferential direction groove;

wherein:

a tire contour portion intersects an end portion of said shoulder and said groove floor, an inclined portion of said tire contour portion and a shoulder side groove wall surface of said tire contour portion intersecting a tire transverse direction outermost portion at a shoulder side curved portion,

a sidewall side groove wall surface of said thin groove intersects said groove floor, said sidewall side groove wall surface and said buttress intersecting at a sidewall side end portion, said tire transverse direction outermost portion being disposed further toward a tire radial direction inner side than said sidewall side end portion, such that the tire transverse direction outermost portion and the sidewall side end portion are located in the same radial plane perpendicular to the axis of rotation of the tire,

a first tire radial direction distance is from a tire radial direction outermost portion of said tread to said tire transverse direction outermost portion, a second tire radial direction distance being from said tire radial direction outermost portion of said tread to said sidewall side end portion, the difference between said first and second tire radial direction distances being in a range between 2 millimeters and 10 millimeters,

said thin groove is continuous in a tire circumferential direction,

the end portion of the shoulder is closer to a width center of the tire in a width direction than the entire thin groove,

said sidewall side end portion of the sidewall side groove wall surface of the thin groove is radially inside said end portion of said shoulder,

said sidewall side groove wall surface includes a sidewall side curved portion at a position facing said shoulder side curved portion, and

said sidewall side end portion of the sidewall side groove wall surface of the thin groove contacts said inclined portion when the buttress is deformed by a lateral force.

8. The pneumatic radial tire according to claim 7 , wherein the sidewall side groove wall surface of the thin groove is formed parallel to the tire contour portion.

9. The pneumatic radial tire according to claim 7 , wherein the thin groove extends from the groove floor in an outward direction with respect to both a tire radial direction and a tire width direction, and opens outwardly in a meridional cross-section.

10. A pneumatic radial tire having a thin groove continuous in a tire circumferential direction at a buttress formed between a shoulder of a tread and a sidewall, comprising:

a tire contour portion that is formed between an end portion of the shoulder and a groove floor of the thin groove,

wherein a tire transverse direction outermost portion at a shoulder side curved portion is disposed further toward a tire radial direction inner side than a sidewall side end portion of a sidewall side groove wall surface of the thin groove, such that the tire transverse direction outermost portion is disposed further toward the tire transverse direction inner side than the sidewall side end portion,

wherein the tire contour portion includes an inclined portion from the end portion of the shoulder toward the thin groove and a shoulder side groove wall surface of the thin groove,

wherein the tire transverse direction outermost portion is an intersection of the inclined portion and the shoulder side groove wall surface at the shoulder side curved portion,

wherein the end portion of the shoulder is closer to a width center of the tire in a width direction than the entire thin groove,

wherein said sidewall side end portion of the sidewall side groove wall surface of the thin groove is radially inside said end portion of said shoulder,

wherein the sidewall side groove wall surface of the thin groove is formed further to a tire radial direction outer side than the shoulder side curved portion of the tire contour portion, and includes a portion at a position facing the shoulder side curved portion of the tire contour portion,

wherein said sidewall side end portion of the sidewall side groove wall surface of the thin groove contacts said inclined portion when the buttress is deformed by a lateral force, and

wherein the thin groove extends from the groove floor in an outward direction with respect to both a tire radial direction and a tire width direction, and opens outwardly in a meridional cross-section; and

wherein the distance between the sidewall side groove wall surface and the inclined portion increases towards the outer side in the tire radial direction.

11. A pneumatic radial tire having a thin groove continuous in a tire circumferential direction at a buttress formed between a shoulder of a tread and a sidewall, comprising:

a tire contour portion that is formed between an end portion of the shoulder and a groove floor of the thin groove,

wherein a tire transverse direction outermost portion at a shoulder side curved portion is disposed further toward a tire radial direction inner side than a sidewall side end portion of a sidewall side groove wall surface of the thin groove, such that the tire transverse direction outermost portion is disposed further toward the tire transverse direction inner side than the sidewall side end portion,

wherein a difference between a first tire radial direction distance from a tire radial direction outermost portion of the tread to the tire transverse direction outermost portion and a second tire radial direction distance from the tire radial direction outermost portion of the tread to the sidewall side end portion is in a range between 2 millimeters and 10 millimeters, and

wherein the end portion of the shoulder is closer to a width center of the tire in a width direction than the entire thin groove,

wherein said sidewall side end portion of the sidewall side groove wall surface of the thin groove is radially inside said end portion of said shoulder,

wherein the sidewall side groove wall surface of the thin groove is formed further to a tire radial direction outer side than the shoulder side curved portion of the tire contour portion, and includes a portion at a position facing the shoulder side curved portion of the tire contour portion,

wherein said sidewall side end portion of the sidewall side groove wall surface of the thin groove contacts an inclined portion of the tire contour portion when the buttress is deformed by a lateral force, and

wherein the thin groove extends from the groove floor in an outward direction with respect to both a tire radial direction and a tire width direction, and opens outwardly in a meridional cross-section; and

wherein the distance between the sidewall side groove wall surface and the inclined portion increases towards the outer side in the tire radial direction.

12. A pneumatic radial tire comprising:

a buttress between a shoulder of a tread and a sidewall, and a thin groove extending into said buttress to a groove floor,

wherein:

a tire contour portion intersects an end portion of said shoulder and said groove floor, an inclined portion of said tire contour portion and a shoulder side groove wall surface of said tire contour portion intersecting a tire transverse direction outermost portion at a shoulder side curved portion,

a sidewall side groove wall surface of said thin groove intersects said groove floor, said sidewall side groove wall surface and said buttress intersecting at a sidewall side end portion, said tire transverse direction outermost portion being disposed further toward a tire radial direction inner side than said sidewall side end portion, such that the tire transverse direction outermost portion is disposed further toward the tire transverse direction inner side than the sidewall side end portion,

a first tire radial direction distance is from a tire radial direction outermost portion of said tread to said tire transverse direction outermost portion, a second tire radial direction distance being from said tire radial direction outermost portion of said tread to said sidewall side end portion, the difference between said first and second tire radial direction distances being in a range between 2 millimeters and 10 millimeters,

said thin groove is continuous in a tire circumferential direction, and

the end portion of the shoulder is closer to a width center of the tire in a width direction than the entire thin groove,

said sidewall side end portion of the sidewall side groove wall surface of the thin groove is radially inside said end portion of said shoulder,

said sidewall side groove wall surface includes a portion at a position facing said shoulder side curved portion,

said sidewall side end portion of the sidewall side groove wall surface of the thin groove contacts said inclined portion when the buttress is deformed by a lateral force, and

the thin groove extends from the groove floor in an outward direction with respect to both a tire radial direction and a tire width direction, and opens outwardly in a meridional cross-section; and

wherein the distance between the sidewall side groove wall surface and the inclined portion increases towards the outer side in the tire radial direction.