Patent ID: 6953333

Claim:
An extruder head for extrusion blow-molding plastic containers, comprising: a ring gap nozzle having a mandrel and a ring-shaped nozzle body; an elastically deformable sleeve; and setting devices for radially deforming the elastic sleeve; whereby the sleeve arranged at the end on the nozzle outlet side defines an annular gap whose width is variable by axial setting movements of the mandrel and/or nozzle body, and whose geometry can be influenced by deforming the sleeve while a hose-like preformed blank is being extruded; and whereby the sleeve is radially movably guided on sliding surfaces supporting the sleeve in the upward and downward directions; characterized in that the sleeve arranged in the body of the nozzle has a conical widening toward the end on the nozzle outlet side and that the inside diameter (d 1 ) of the sleeve measured on the upper face is smaller than the inside diameter (d 2 ) of the sleeve on the nozzle outlet; and that the wall profile of the sleeve and the height of the points of force application of the setting devices along the sleeve, said points of force application being located out of center in the longitudinal direction of the sleeve, are coordinated with one another in such a way that the upper face of the sleeve guided on a sliding surface of the nozzle body at least approximately maintains its plane parallelism in relation to the sliding surface when the sleeve is deformed.