PNEUMATIC TYRE AND MANUFACTURING METHOD THEREFOR

摘要

The uniformity of a tyre is enhanced by improving the shape of the wire winding forming the bead core. The bead core (5) of a pneumatic tyre (1) comprises a wire winding (10) having a plurality of bead wire (10a) layers formed in the radial direction of the tyre by winding a single bead wire (10a) several times around the rotational axis (CL) of the tyre in a spiraling fashion. The wire winding (10) has a first portion (13) and a second portion (14). The first portion (13) has a plurality of bead wire (10a) layers extending in the circumferential direction of the tyre at a fixed radius (R) from the rotational axis (CL) of the tyre. The second portion (14) has a plurality of bead wire (10a) layers extending in the circumferential direction of the tyre at radii (R) which vary in distance from the rotational axis (CL) of the tyre.