| 摘要 |
In tread-width-direction cross section under a standard internal pressure and no load condition, a point B is an outermost point of overlapping area in tread-width-direction, a line CC is a line passing through an outermost point CT of carcass layer in tread-width-direction and extending along tread-width-direction, a point C is a point of tire surface through the line CC, a line segment BW is a line segment extending in tread-width-direction from an equator center line to point B, a line segment CW is a line segment extending along tread-width-direction from equator center line to point C, and a line segment BC is a line segment connecting between point B and C. A ratio BW/CW between a length of BW and CW is not less than 0.6 and not more than 0.8. An angle θ formed by BC and CW is not less than 50° and not more than 70°. |
| 主权项 |
1. A pneumatic tire comprising:
a pair of bead portions each including a bead toe that is an inner end portion of the bead portion in the tire radial direction, a bead core, and a bead filler adjoining the bead core, the bead filler enhancing a rigidity of the bead portion, a carcass layer laid between the pair of bead portions, the carcass layer being bent outward in the tread width direction so as to cover the bead core and the bead filler; a tread portion positioned on an outer side of the carcass layer in a tire radial direction; and at least two belt layers positioned between the carcass layer and the tread portion, wherein the at least two belt layers form an overlapping area where two of the at least two belt layers overlap one another, in a tread width direction cross section mounted to a standard rim under a standard internal pressure and no load condition,
a point B is an outermost point of the overlapping area in a tread width direction,a straight line CC is a straight line passing through an outermost point C′ of the carcass layer in the tread width direction and extending along the tread width direction,a point C is a point of a tire surface through which the straight line CC passes,a line segment BW is a line segment extending in the tread width direction from an equator center line to the point B,a line segment CW is a line segment extending along the tread width direction from the equator center line to the point C, anda line segment BC is a line segment connecting between the point B and the point C,a point U is an outermost point of the bead filler in the tire radial direction,a point T is an innermost point of the bead toe in the tire radial direction,a point S is a point of the tire surface through which the equator line passes,a point D is an outermost point of the overlapping area in the tire radial direction,a point E is an outermost point of the tire surface in the tire radial direction,a point F is a point of the tire surface at which a straight line extending in the tire radial direction from the point B crosses the tire surface, a ratio BW/CW between a length of the line segment BW and a length of the line segment CW is equal to or larger than 0.6 and equal to or smaller than 0.8, and an angle θ formed by the line segment BC and the line segment CW is equal to or larger than 50° and equal to or smaller than 70°; a radial direction difference CH is a radial direction difference between the point C and the point T, a radial direction difference SH is a radial direction difference between the point S and the point T, and the ratio CH/SH is equal to or smaller than 0.50; a radial direction difference BD is a radial direction difference between the point B and the point D in the tire radial direction, and the ratio BD/BW is equal to or larger than 0.02 and equal to or smaller than 0.1; a radial direction difference EF is a radial direction difference between the point E and the point F in the tire radial direction, and the ratio EF/BW is equal to or larger than 0.05 and equal to or smaller than 0.15; a radial direction difference UH is a radial direction difference between the point U and the point T, and the radial direction difference UH is equal to or smaller than 25 mm. |
