Tire manufacture

摘要

In moulding the tread portion of a pneumatic tire to have a breaker structure incorporated therein the breaker is built in an annular mould cavity to have a radially outermost 90 DEG ply consisting of parallel cords extending axially of the cavity, and uncured rubber is introduced into the cavity through an annular gate surrounding the cavity so as to spread axially of the cavity. As the introduced uncured rubber does not move circumferentially of the cavity it has no tendency to displace the breaker cords.