A tire having uniform inflation growth is provided. The tire includes a body ply that is displaced from the conventional equilibrium curve along the bead, sidewall, and shoulder portions of the tire in a manner that provides more uniform inflation growth from bead portion to bead portion. Such construction reduces load sensitivity, reduces or eliminates the tire break-in period, and/or decreases the propensity for cracking—particularly along a groove bottom of the tread in the shoulder.

The tire comprises a tread, a crown reinforcement and at least one crown layer. The crown layer has an axial width (L.sub.2) that is at least two-thirds of a maximum axial width (L.sub.1) of the tire and has a concave portion with axial limits (M.sub.2, M′.sub.2) on either side of an equatorial plane (XZ). The tire further includes a carcass reinforcement which has at least one carcass layer with a concave portion that has axial limits (M.sub.3, M′.sub.3) on either side of the equatorial plane (XZ). The radial distance (d) between the respective concave portions is at a maximum in the equatorial plane (XZ) and decreases continuously from the equatorial plane (XZ) as far as the axial limits (M.sub.2, M′.sub.2) of the said concave portions axially closest to the equatorial plane (XZ), where it reaches a minimum value (d.sub.M).

A pneumatic tire comprises a carcass layer, a belt layer radially outward of the carcass layer, and a tread rubber radially outward of the belt layer. The belt layer includes an angle belt having a belt angle ≥45° and ≤70° in absolute values, a pair of cross belts having belt angles of ≥10° and ≤45° in absolute values and having belt angles of mutually opposite signs, and a reinforcing layer having a belt angle within ±5° relative to a circumferential direction. A width Ws of the reinforcing layer and a cross-sectional width Wca of the carcass layer satisfy 0.60≤Ws/Wca≤0.70. The cross belts are radially outward of the large angle belt. The reinforcing layer is radially inward of the pair of cross belts. A width Wb2 of a wider cross belt of the pair and Wca satisfy 0.79≤Wb2/Wca≤0.89.

Tire comprising major grooves with a depth at least equal to 4 mm and with a width at least equal to 1 mm. The radially outermost working layer (41) comprises at least one undulation (412). The undulation (412) is such that the undulation (412) portion of the working layer (41) represents at least 10% of the surface of the working layer (41), has an amplitude of at least 1 mm and is radially on the outside of the points of the working layer (41) that are in line with the bottom face (243) of the major groove (24) closest (412). All the layers of material (3, 6, 7) making up the radial stack of the crown structure (S) have mean surfaces parallel to that of the radially outermost working layer (41).

The present invention aims to provide a pneumatic tire with sufficiently reduced rolling resistance. The pneumatic tire according to the present invention including a carcass having a carcass main portion extending from a tread portion via a sidewall portion to a bead portion in a toroidal shape and locked on a bead core embedded in the bead portion, and a belt disposed on a crown portion outer peripheral side of the carcass, characterized in that, when mounted on an applicable rim and put under a predetermined internal pressure no-load condition, a minimum value R1 of a curvature radius of a tire width direction cross-section in a tire radial direction outer portion of the carcass main portion positioned on an tire radial direction outer side than a position where a distance measured from a tire radial direction inner end of the carcass outwardly in the tire radial direction becomes ½ of a carcass cross-sectional height is 0.6 times or less of a minimum value R2 of the curvature radius of the tire width direction cross-section of a portion that, in the tire radial direction inner portion of the carcass main portion positioned on the tire radial direction inner side than the tire radial direction outer portion, bulges out in the tire width direction.

A low compaction cantilevered tire construction is provided which is designed for use at relatively low inflation pressures and which has sidewalls with a relatively uniform bending resistance through the majority of the sidewall. When the tire is placed under high loads at low inflation pressures the sidewall deflects substantially radially and allows the tread portion of the tire to maintain its intended shape thus improving the contact area of the tire and providing a tire having a relatively high contact area and thus relatively low soil compaction for a given loading.

A tire having uniform inflation growth is provided. The tire includes a body ply that is displaced from the conventional equilibrium curve along the bead, sidewall, and shoulder portions of the tire in a manner that provides more uniform inflation growth from bead portion to bead portion. Such construction reduces load sensitivity, reduces or eliminates the tire break-in period, and/or decreases the propensity for cracking—particularly along a groove bottom of the tread in the shoulder.

A radial tire for an aircraft, the radial tire having a rim diameter of 20 inches or less includes a pair of bead portions; a pair of sidewall portions extending outward from the bead portions in a substantially radial direction; a tread portion that couples together respective radial outer ends of the sidewall portions; a toroidal carcass layer reinforcing a portion between bead cores embedded in the bead portions; a belt layer and a tread that are sequentially laminated on an outer side of the carcass layer in the radial direction, wherein a value M obtained by dividing a tire external diameter D by a distance L between bead heels of the bead portions is in a range of from 4.1 to 5.4.

A pneumatic tire is provided where a profile line in a tire meridian cross section of a center land portion defined by circumferential grooves and located on a tire equator is curved projecting outward in a tire radial direction. A carcass layer and a reinforcing layer include a recess portion curved projecting inward in the tire radial direction in a bottom region of the center land portion.

In a pneumatic tire mountable on a 5°-tapered rim, a bottom of a bead core is inclined from 0°-5° in a direction in which the bottom diverges toward an outer side in a radial direction as the bottom extends from an inner side in the width direction toward an outer side in the width direction. Each bead portion includes a base, a toe, and a heel. The base is inclined from 8°-12° in a direction in which the bead base portion diverges toward the outer side in the radial direction as the base extends from the inner side toward the outer side in the width direction. The heel has a radius of curvature from 25-30 mm. A rim cushion rubber has a modulus at 100% elongation within a range from 5.0-8.0 MPa. The toe has a displacement between before and after mounting on the rim from 9.0-13.5 mm.