Assembly forming a bead core for a lorry tyre, lorry tyre comprising such an assembly and method for producing such an assembly

摘要

The assembly forming a bead core (23) is characterised in that it comprises several turns, clamped together in a bundle, with a strand formed of a continuous steel wire, of circular transverse section, and of a diameter of at least 1.65 mm, the wire being drawn to this diameter without intermediate patenting during drawing and exhibiting a mechanical strength of at least 1900 MPa. The method consists in the fact that a steel wire of high strength is drawn to a strand diameter of 1.65 mm or more, then it is used to wind an assembly forming a bead core 23, by winding this wire into several turns around an annular jig so as to form an assembly forming a bead core of the desired transverse section, this bead core having a mechanical strength of at least 1900 MPa and being wound directly around the jig without patenting between the drawing and winding operations. IMAGE