Bead reinforcement for heavy vehicle pneumatic tire has additional discontinuous reinforcing elements in concentric circles and mechanically coupledFR2840562A1

摘要

Tyre for vehicles carrying heavy loads, comprising in at least one bead (1) an additional reinforcement (9) composed of a plurality of discontinuous reinforcing elements (920, 921, 922), these discontinuous reinforcing elements being orientated essentially circumferentially to form a plurality of circles C, CI, C2 concentric on the rotation axis of the tyre mounted on its rim, each circle being defined by a mean radius (R, Rl, R2) measured relative to the said rotation axis, the said tyre being characterised in that: each discontinuous reinforcing element (920) of length L0 located on a circle C of radius R is mechanically coupled over coupling lengths LI 1 and LI2 with two discontinuous reinforcing elements (921) located on a circle CI of radius Rl, this circle being immediately adjacent to the circle C, the coupling length LI 1 being between 55 and 75% of L0 and the coupling length LI2 being between 10 and 30% of L0; each discontinuous reinforcing element (920) on the same circle C of radius R is mechanically coupled over coupling lengths L21 and L22 with two discontinuous reinforcing elements (922) located on a circle C2 of radius R2 immediately adjacent to the circle CI, the coupling length L21 being between 20 and 40% of L0 and the coupling length L22 being between 45 and 65% of L0.