PRODUCTION OF TIRE AND BEAD APEX RUBBER EXTRUDER

摘要

PURPOSE:To form a wt. reduced tire by arranging a large number of pin materials with a specific diameter value mutually extending through a rubber passing hole to be interrupted on the outlet side of the hole and fixed to an extrusion nozzle substrate on the inlet side of the hole to the rubber passing hole of the extrusion nozzle substrate and setting the ratio of the opening area of an extrusion port and the sum total of the cross-sectional area of the pin materials to a specific value. CONSTITUTION:Raw rubber made viscous is passed through a passing hole 3 and a lower piece having a large number of holes continuing in its longitudinal direction by a large number of pin materials 5... is extruded so as to have the contour having the cross-sectional shape of the lower piece of a bead apex. Each of the pin materials 5 has a diameter of 1-3mm and the cross-sectional area on the side of the interrupted end thereof is made larger than that on the inlet side 1 thereof and the holes of the extruded raw lower piece can be accurately formed. The ratio SIGMAs/S of the sum total SIGMAs of the cross-sectional areas (s) of the pin materials 5 in an extrusion port 6 and an opening area S is set to 0.1-0.7 to form a homogenous raw lower piece. An upper piece is formed by a rubber extruder only of a nozzle substrate and the raw upper and lower pieces are bonded to form a raw bead apex.