Tire assembly having an improved bead and a mounting rim

An assembly comprising a tire and a mounting rim, the tire having an axis of rotation and comprising:

• two beads adapted to come into contact with the mounting rim, each bead comprising at least one annular reinforcing structure, each annular reinforcing structure having an axially innermost point, the two annular reinforcing structures defining a median plane of the tire, perpendicular to the axis of rotation of the tire and situated equal distances from the annular reinforcing structures of each bead;
• two sidewalls extending the beads radially outwards, the two sidewalls meeting in a crown comprising a crown reinforcement comprising two plies each comprising reinforcing elements and being in contact with one another over at least part of the width of the crown, this part extending on each side of the median plane of the tire, between two contact ends, the crown reinforcement being surmounted by a tread;
• at least one carcass reinforcement extending from the beads through the sidewalls as far as the crown, the carcass reinforcement comprising a plurality of carcass reinforcing elements and being anchored in the two beads by a turn-up around the annular reinforcing structure so as to form, within each bead, a main strand and a turn-up, each turn-up extending radially outwards as far as an end situated a radial distance DRE from a radially innermost point of the annular reinforcing structure of the bead, the radial distance DRE being greater than or equal to 5% and less than or equal to 20% of a radial height H of the tire;
• wherein each bead comprises a filler formed of a rubber composition, the filler being situated, at least partially, radially on the outside of the annular reinforcing structure and at least partially between the main strand and the turn-up of the carcass reinforcement, the filler extending radially as far as a radial distance DBE from the radially innermost point of the annular reinforcing structure of the bead, the radial distance DBE being less than or equal to 10% of the radial height H of the tire,
• wherein at least one sidewall of the tire further comprises a stiffening reinforcement having a radially inner end and a radially outer end, the stiffening reinforcement being formed of a plurality of metallic reinforcing elements oriented at an angle less than or equal to 10 degrees with respect to the circumferential direction, this stiffening reinforcement being positioned in such a way that a distance DAE between a radially innermost point of the annular reinforcing structure and the radially outer end of the stiffening reinforcement is greater than or equal to 20% and less than or equal to 40% of the radial height H of the tire and that a distance DAI between the radially innermost point of the annular reinforcing structure and the radially inner end of the stiffening reinforcement is greater than or equal to 5% and less than or equal to 15% of the radial height H of the tire,
• wherein a portion of rubber composition is positioned axially on the outside of the stiffening reinforcement, wherein a thickness (E2) of this portion of rubber composition, measured perpendicular to the stiffening reinforcement, is greater than or equal to 1.2 mm at all points;
• wherein a ratio D2/D1 is greater than or equal to 1, where D1 denotes an axial distance between each contact end and the median plane of the tire and D2 is an axial distance between the axially innermost point of the annular reinforcing structure and the median plane of the tire, the distances D1 and D2 being measured when the tire is mounted on the mounting rim and inflated to a service pressure;
• wherein the tire further comprises an decoupling ply made of a rubber composition and positioned axially between the carcass reinforcement and the stiffening reinforcement, the decoupling ply having a radially inner end and a radially outer end, the decoupling ply having a thickness (E1) greater than or equal to 0.8 mm, this thickness being measured perpendicular to the stiffening reinforcement;
• wherein the radially inner end of the stiffening reinforcement is radially on the outside of a radially inner end of the decoupling ply, a radial distance (DB) between these two ends being less than 10 mm, and
• wherein the radially outer end of the stiffening reinforcement is radially on the inside of a radially outer end of the decoupling ply, a radial distance (DC) between these two ends being less than 10 mm.