Patent ID: 6951233

Claim:
An apparatus for making part of an electrically conductive tread having an insert of a conductive rubber mix, comprising a main extruder which comprises an extrusion orifice comprising a wall which cooperates with a roller and having a main extrusion head provided at its end with a main nozzle for extruding a tread comprising a non-vulcanized non-conductive mix, and a micro-extruder, mounted on a support and comprising an extrusion head, provided at its end with a nozzle for extruding the insert having a desire profile and trace, said nozzle being placed in the main extrusion head of the main extruder, the nozzle being placed in a space between an upper fixed part of the main extruder and a lower part of the main extruder facing said upper fixed part, and wherein the conductive rubber mix to be extruded flows in the flow of non-conductive rubber mix, before being extruded through the main nozzle, and wherein the conductive rubber mix and the non-conductive rubber mix flow in the same direction and the end of the nozzle for extruding the insert is applied against the lower part so that the extruded insert extends through the entire thickness of the extruded non-conductive rubber mix.