Provided is a coupling unit for coupling a tire to a rim, the coupling unit including an upper surface, a lower surface, and side surfaces, in which a maximum length of the coupling unit is larger than a distance between both hooks of the rim, the side surfaces include sliding areas that are slidable with respect to the hooks of the rim such that the coupling unit is easily inserted into the rim while the coupling unit is being inserted into the rim, and in a state in which the coupling unit is completely inserted into the rim, at least a part of the upper surface is in surface contact with lower surfaces of the hooks to prevent the coupling unit from being separated from the rim.

Provided is a coupling unit for coupling a tire to a rim, the coupling unit including an upper surface, a lower surface, and side surfaces, in which a maximum length of the coupling unit is larger than a distance between both hooks of the rim, the side surfaces include sliding areas that are slidable with respect to the hooks of the rim such that the coupling unit is easily inserted into the rim while the coupling unit is being inserted into the rim, and in a state in which the coupling unit is completely inserted into the rim, at least a part of the upper surface is in surface contact with lower surfaces of the hooks to prevent the coupling unit from being separated from the rim.

Provided is a coupling unit for coupling a tire to a rim, the coupling unit including an upper surface, a lower surface, and side surfaces, in which a maximum length of the coupling unit is larger than a distance between both hooks of the rim, the side surfaces include sliding areas that are slidable with respect to the hooks of the rim such that the coupling unit is easily inserted into the rim while the coupling unit is being inserted into the rim, and in a state in which the coupling unit is completely inserted into the rim, at least a part of the upper surface is in surface contact with lower surfaces of the hooks to prevent the coupling unit from being separated from the rim.

In a tire, in a cross-section of a core of a bead taken at a plane perpendicular to the circumferential direction, two or more rows of wire cross-sections aligned in the axial direction are stacked. When the radially innermost row is a first row and a row immediately outside the innermost row in the radial direction is a second row, the number of the cross-sections of the wire in the first row is less than that in the second row. An inner end of the second row is axially inward of a line drawn from an inner end of the first row and is perpendicular to a direction in which the first row extends. In the cross-section of the core taken at a plane perpendicular to the circumferential direction, an angle between a bottom side of the core and a bead base line is 2 to not greater than 9.

In a tire, in a cross-section of a core of a bead taken at a plane perpendicular to the circumferential direction, two or more rows of wire cross-sections aligned in the axial direction are stacked. When the radially innermost row is a first row and a row immediately outside the innermost row in the radial direction is a second row, the number of the cross-sections of the wire in the first row is less than that in the second row. An inner end of the second row is axially inward of a line drawn from an inner end of the first row and is perpendicular to a direction in which the first row extends. In the cross-section of the core taken at a plane perpendicular to the circumferential direction, an angle between a bottom side of the core and a bead base line is 2 to not greater than 9.

A rolling assembly comprises a tire (2) having two beads (21), a rim (3) and at least one flexible extender (1) intended to provide the connection between one of the beads (21) and the rim (3), the rim having a rim flange (32), said extender (1) comprising an axially inner end (10), an axially outer end (11) and a body (12) that is oriented mainly axially and is disposed between said axially outer end (11) and said axially inner end (10), said axially inner end (10) being fixed in place on said rim, said extender (1) having an extender seat (13) intended to receive a tire (2) bead (21), said extender seat being extended axially towards the outside by a shoulder that axially fixes said tire (2) bead (21) in place, said tire (2) bead (21) having an axial width WB at the interface of the bead (21) with the extender seat (13), characterized in that said rim flange (32) extends axially under the bead (21) by a distance S such that the ratio S/WB is greater than 0.1.

A rolling assembly comprises a tire (2) having two beads (21), a rim (3) and at least one flexible extender (1) intended to provide the connection between one of the beads (21) and the rim (3), the rim having a rim flange (32), said extender (1) comprising an axially inner end (10), an axially outer end (11) and a body (12) that is oriented mainly axially and is disposed between said axially outer end (11) and said axially inner end (10), said axially inner end (10) being fixed in place on said rim, said extender (1) having an extender seat (13) intended to receive a tire (2) bead (21), said extender seat being extended axially towards the outside by a shoulder that axially fixes said tire (2) bead (21) in place, said tire (2) bead (21) having an axial width WB at the interface of the bead (21) with the extender seat (13), characterized in that said rim flange (32) extends axially under the bead (21) by a distance S such that the ratio S/WB is greater than 0.1.

A pneumatic tire including a tread portion, a pair of sidewall portions, a pair of bead cores, a first ply, and a second ply being discontinuous and having a pair of ply pieces. The first ply includes a central portion positioned in the tread portion, a pair of side portions extending from opposite ends of the central portion, and a pair of folded-up portions folded up around the respective pair of bead cores. The pair of ply pieces each includes a side portion extending from an inner end, and a folded-up portion folded up around any one of the pair of bead cores. In each of the sidewall portions, the first ply has a plurality of first cords extending in the tire radial direction, and the pair of ply pieces each has a plurality of second cords extending at an angle from the first cords.

A pneumatic tire including a tread portion, a pair of sidewall portions, a pair of bead cores, a first ply, and a second ply being discontinuous and having a pair of ply pieces. The first ply includes a central portion positioned in the tread portion, a pair of side portions extending from opposite ends of the central portion, and a pair of folded-up portions folded up around the respective pair of bead cores. The pair of ply pieces each includes a side portion extending from an inner end, and a folded-up portion folded up around any one of the pair of bead cores. In each of the sidewall portions, the first ply has a plurality of first cords extending in the tire radial direction, and the pair of ply pieces each has a plurality of second cords extending at an angle from the first cords.

A run-flat tire comprises a tread portion, sidewall portions, bead portions, and a carcass ply extending between the bead portions. The sidewall portions are each provided therein with a sidewall reinforcing rubber layer having a crescent-shaped cross sectional shape and disposed on the axially inside of the carcass ply. The sidewall portions are each provided in the axially outer surface thereof with a rim protector which projects radially outward most on the radially outside of the radially inner edge of the sidewall reinforcing rubber layer. The bead portions are each provided therein with an axially inside core and an axially outside core between which each radially inner edge portion of the carcass ply is secured. When measured along a normal line drawn normally to the carcass ply from an apex of the rim protector, the thickness of the sidewall reinforcing rubber layer is in a range of from 29% to 35% of the thickness of the tire.