| 摘要 |
PURPOSE:To heighten the steering stability and durability of a tire, by providing a tongue-shaped bead apex and a prescribed breaker so that the breaker is located on the crown of the tire and the apex is located between the bent- back part of the bead of the tire and its toroidal no-ply carcass whose cord extends at a prescribed angle as to the circumferential direction of the tire. CONSTITUTION:The no-ply part of a carcass 1, whose cord extends at an angle of 20 to 80 deg. as to the circumferential direction of a tire, is bent back around a bead wire 4 to make the carcass 1 toroidal. A tongue-shaped bead apex 3 is provided in a part surrounded by the carcass 1 and its bent-back end 5. The bent- back end 5 is located near a tread shoulder S. A breaker 2 is provided outside the carcass 1 at the crown of the tire so that the breaker intersects the carcass cord. The width l of the breaker 2 is set equal to 80 to 10% of that L of the tread 6. According to this constitution, the side portions and tread 6 of the tire are reinforced and ride comfortableness, steering stability and durability are enhanced. |
