| 摘要 |
PURPOSE:To improve durability in a bead part, by setting up a second reinforcing layer's lower end in position between a bead core side face and a rim flange upper end, while constituting it so as to be covered with a carcass and a first reinforcing layer's rolled-in end turned up, in case of a radial tire for heavy- duty use such as a motor bus or the like. CONSTITUTION:A carcass rolled-in end 12 is made into a high-ply turnup construction situated in a higher position than a first reinforcing layer's rolled-in end 13. A second reinforcing layer 17 is made up of one ply or composite plies of a steel or textile cord layer, while a turnup part 19 is turned up outward to a tire section from a higher position 22 than the carcass rolled-in end 12 at the upper end of a covering part 18, covering a carcass 6 and these rolled-in ends 12 and 13 of the first reinforcing layer 11. In addition, a lower end 20 of the second reinforcing layer 17 is situated in position between the side position of a bead core 5 and the upper side end vicinity of a rim flange 21. With this constitution, a shortage of rubber quantities in a bead bottom part is prevented and, what is more, durability in a bead part is thus improvable. |
