| 摘要 |
PURPOSE:To prevent the slip-off of a bead and improve safety in traveling by forming a bead core by binding a plurality of bead wires having a circular section and arranging the prepared bead wires in a prescribed width in the direction of the inside diameter, forming the inside-diameter step difference. CONSTITUTION:An annular bead core BC is formed by integrally forming the inside and outside band-shaped bead cores 2 and 3 each of which is formed by binding a plurality of bead wires having a circular section in parallel so that a step difference is formed. The inside diameter difference (a) in the radial direction which is formed between the inside and outside cores 2 and 3 is set 0.3- 2.7mm., and the ratio b/c between the width (b) of the bead core on the projection side in the direction of inside diameter and the width (c) of the whole bead core is set to 0.2-0.8. With such constitution, the slip-off of the bead is prevented, and the safety in traveling can be improved. |
