Patent ID: 6524416
Filing Date: 2003-02-25
Classification: B29D

Abstract:
In a method of producing a pneumatic tire comprising a tire carcass, including a pair of annular beads, at least one flexible ply having side edges wrapped around the beads, a pair of sidewalls, the edges of the carcass ply forming turn-ups terminating radially above the beads, and an apex filler in contact with the outer periphery of each bead and extending radially outwardly therefrom between the carcass ply and the turn-up, the method comprising the steps of:extruding the apex filler as an elastomeric extrusion having a generally triangular cross section and comprising a base and a pair of sides converging at a peak; coiling the elastomeric strip into a spiral shaped coil having a triangular cross-sectional shape with a inner diameter (Dc) of the extrusion being smaller than the outer diameter (DB) of the annular bead whereby the base of the extrusion is compressed and the peak of the extrusion is stretched; unwinding the spiral shaped coil to increase the diameter of the coil; and wrapping the unwound spiral shaped coil with the increase in diameter around an outer diameter of the annular bead to form an apex filler/annular bead subassembly.