| 摘要 |
PURPOSE:To reduce a tire weight without decreasing the rigidity of a bead portion and steering stability, by providing a carcass whose rolling-up portion is integrated with its body portion, providing a reinforcing layer consisting of plural high-tension cords which extend along the rolling-up portion, and also arranging the body portion and the rolling-up portion adjacently to each other. CONSTITUTION:A carcass 6, is furnished with a rolling-up portion 6B which can be rolled up around the bead core 5 from the inside to outside of tire along its body portion 6A extending from a tread portion 2 to the bead core 5 of a bead portion 4 through a side wall portion 3. Meantime, two reinforcing layers 9A and 9B are provided along the rolling-up portion 6B on its axially outer side. The heights H9ad and H9bd of the radially lower ends of respective reinforcing layers 9A and 9B, are set less than the height Hf of a lower point X1 which is the upper edge of a rim flange 11. The upper ends have heights H9au and H9bu, exceeding the height Hs of an upper point X2 which is equal to 0.25 time the height Ht of tire section. Furthermore, the body portion 6A and the rolling-up portion 6B are moved close to each other on the radially outer side of the lower point X1. |
