| 摘要 |
The invention relates to improvements to the endurance of the beads of a radial tyre for a heavy vehicle of construction plant type, by reducing the cracking that starts at the end of the turned-back portion and spreads through the coating, edging and filling polymer materials. According to the invention, a transition element (25), made of a transition polymer material, is at least partially in contact, over its axially exterior face, with the edging polymer material (22) and, over its axially interior face, with a filling polymer material (23b), the radially exterior (E25) and radially interior (I25) ends of the transition element are respectively radially on the outside and radially on the inside of the end of the turned-back portion and the elastic modulus at 10% elongation of the transition polymer material is somewhere between the respective moduli at 10% elongation of the edging polymer material and of the filling polymer material with which the transition element is in contact. |
