Abstract:
A pneumatic radial tire including a carcass; two belt reinforcing layers; and a belt formed by two belt layers. A width of a belt cord intersecting region defined by the two belt layers is set in the range of 65 to 90% of the tire width-W, the maximum width of the belt reinforcing layer is set in the range of 60 to 85% of the tire width. Also, a belt radius ratio, which is a ratio of difference between the radius of the belt at the tire equatorial plane and the radius of the belt at a belt side end position thereof measured from the tire axis in a state where the tire is inflated at the standard inner pressure, with respect to a belt half width, is not larger than 0.06.
Abstract:
The present invention relates to a method of forming at least one circumferential belt layer of a pneumatic tire comprising: winding the strip for a half length of an outer circumferential length of the crown portion of the carcass along the tire equatorial plane from a widthwise inner side of the belt end region; winding the strip for the remaining half length while shifting the strip for the width of the strip from a widthwise inner to outer side; winding the strip for the outer circumferential length of the crown portion of the carcass along the tire equatorial plane; winding the strip for the half length of the outer circumferential length of the crown portion of the carcass while shifting the strip for the width of the strip from the widthwise outer to inner side; and winding the strip for the remaining half length along the tire equatorial plane.
Abstract:
The present invention provides a pneumatic tire having a carcass 11, at least one circumferential belt layer 17 provided on the outer side in the tire radial direction of the carcass 11, and plural intersecting belt layers 18 provided on the outer side in the tire radial direction of the circumferential belt layer 17, at least one of the plural intersecting belt layers having wider belt width in the tire widthwise direction than the circumferential belt layer 17, comprising: at least one layer of end-portion circumferential belt 15 provided in respective tire widthwise tread end regions on the outer side of the carcass 11 and on the inner side of the circumferential belt layer 17 in the tire radial direction; and at least one layer of slant belt 16 provided in the tire widthwise tread central region on the outer side of the carcass 11 and on the inner side of the circumferential belt layer 17 in the tire radial direction.
Abstract:
The present invention provides a tire with a belt having relatively high durability by improving fatigue resistance of cords at end portions of a circumferential belt layer, in particular, and especially proposes a radial tire for heavy load, having a relatively small aspect ratio. For this purpose, the present invention provides a tire having a carcass as a skeleton provided in a toroidal shape over a pair of bead portions, a belt disposed on the outer side in the radial direction of the carcass, and a tread disposed on the outer side in the radial direction of the belt, the belt including: at least one layer of circumferential belt layer disposed on the outer side in the radial direction of a crown portion of the carcass and formed of a number of cords extending along the equatorial plane of the tire and coating rubber thereon; and at least two layers of slant belt layers disposed on the circumferential belt layer and each formed of a number of cords extending in a direction inclined with respect to the equatorial plane O of the tire and coating rubber thereon, characterized in that: a width of the circumferential belt layer is no less than 60% of the total width of the tire; a width of at least one of the slant belt layers is wider than the width of the circumferential belt layer; and modulus of elasticity of first cords disposed on an end portion side in the widthwise direction of the circumferential belt layer is lower than modulus of elasticity of second cords disposed on the inner side in the widthwise direction of the first cords.
Abstract:
The present invention provides a pneumatic tire having a carcass 11, at least one circumferential belt layer 17 provided on the outer side in the tire radial direction of the carcass 11, and plural intersecting belt layers 18 provided on the outer side in the tire radial direction of the circumferential belt layer 17, at least one of the plural intersecting belt layers having wider belt width in the tire widthwise direction than the circumferential belt layer 17, comprising: at least one layer of end-portion circumferential belt 15 provided in respective tire widthwise tread end regions on the outer side of the carcass 11 and on the inner side of the circumferential belt layer 17 in the tire radial direction; and at least one layer of slant belt 16 provided in the tire widthwise tread central region on the outer side of the carcass 11 and on the inner side of the circumferential belt layer 17 in the tire radial direction.
Abstract:
The present invention provides a pneumatic radial tire capable of effectively improving belt durability, while ensuring good resistance to wear at a tread surface. The pneumatic radial tire comprises: a carcass 5 of a toroidal shape engagedly held between at least one pair of bead cores 4; two belt reinforcing layers 8a, 8b constituted of a reinforcing element extending in the tire circumferential direction and provided on the outer side of a crown region of the carcass 5 and on the inner side of a tread rubber 7; and a belt 10 formed by two belt layers 9a, 9b and provided on the outer side in the tire radial direction of the belt reinforcing layer, belt cords of one belt layer and those of another belt layer extending in directions opposite to each other with respect to the tire equatorial plane E, wherein the width w1 of a belt cord intersecting region defined by the two belt layers 9a, 9b is set in the range of 65 to 90% of the tire width W, the maximum width w0 of the belt reinforcing layer 8a, 8b is set in the range of 60 to 85% of the tire width W, and a belt radius ratio, which is a ratio of difference (R0-R1) between the radius (R0) of the belt at the tire equatorial plane and the radius (R1) of the belt at a belt side end position thereof measured from the tire axis in a state where the tire is inflated at the standard inner pressure, with respect to a belt half width (w/2), is not larger than 0.06.
Abstract:
The present invention provides a tire with a belt having relatively high durability by improving fatigue resistance of cords at end portions of a circumferential belt layer, in particular, and especially proposes a radial tire for heavy load, having a relatively small aspect ratio. For this purpose, the present invention provides a tire having a carcass as a skeleton provided in a toroidal shape over a pair of bead portions, a belt disposed on the outer side in the radial direction of the carcass, and a tread disposed on the outer side in the radial direction of the belt, the belt including: at least one layer of circumferential belt layer disposed on the outer side in the radial direction of a crown portion of the carcass and formed of a number of cords extending along the equatorial plane of the tire and coating rubber thereon; and at least two layers of slant belt layers disposed on the circumferential belt layer and each formed of a number of cords extending in a direction inclined with respect to the equatorial plane O of the tire and coating rubber thereon, characterized in that: a width of the circumferential belt layer is no less than 60% of the total width of the tire; a width of at least one of the slant belt layers is wider than the width of the circumferential belt layer; and modulus of elasticity of first cords disposed on an end portion side in the widthwise direction of the circumferential belt layer is lower than modulus of elasticity of second cords disposed on the inner side in the widthwise direction of the first cords.