| 摘要 |
<p>A pneumatic tyre comprises a tread portion (10), a pair of sidewall portions (2), a pair of bead portions (12) each with a bead core (11) and a bead apex (3) therein, each sidewall portion (2) being provided on the outer face with means to allow the escape of air between the tyre and a mould for vulcanising the tyre, wherein the air escape means comprises a circumferentially extending vent emboss line (5A) disposed adjacently to a radially outer end (3A) of the bead apex (3) and a circumferentially extending vent groove (7) adjoining the radially outside of the vent emboss line (5A) and having a depth of at least 0.15 mm. Preferably, the vent groove (7) has a width of from 5 to 10 mm and a depth of from 0.2 to 0.5 mm, and the vent emboss line (5A) and vent groove (7) are disposed in a lower sidewall region (2A2) having a substantially straight profile. The bottom (7a) of the vent groove (7) may be substantially parallel to the straight profile (b-c) of the lower sidewall region and the bottom (7a) may be provided with emboss marks (S). <IMAGE></p> |
