| 摘要 |
A tyre has no bead wires but each bead presents (a) an annular element (7) with a longitudinal tensile strength significantly less than that needed for a bead wire of an equivalent sized tyre; (b) at least two layers of reinforcement (8, 9, 10) placed in contact or in proximity to the annular element, where each reinforced layer consists of parallel strands but the strands of adjacent layers are displaced by an angle of up to 10 degrees ; (c) the assembly of reinforcing layers has ultimate tensile strength at least equal to that necessary for a traditional bead wire; (d) the carcass layers are wound around the annular element; and (e) the outer area of the bead has a rubber with a modulus of elastic loss G'' less than 1 MPa and/or the thickness of the rubber is at most 2 mm. |
