Device for manufacturing a tube-like preform having different cross-sections along its length for blow-molding a hollow body of a thermoplastic material

The utility model relates to a device for manufacturing a tube-like preform with different cross-sections along its length for blow-molding a hollow body of a thermoplastic material, in which the plastic is first pressed into a recess in a neck mold (injection molding tool) abutting an annular nozzle for the plastic and then formed into the preform by moving away the neck mold from the annular nozzle; in which a control device for a drive for pressing and moving away of the neck mold and a control device for a drive for changing the outlet gap of the annular nozzle during the moving away of the neck mold from the annular nozzle can be actuated; and in which an increase in speed from zero is provided when the neck mold is lifted from the annular nozzle, the control devices operate during a further moving away section and the control devices operate as path-dependent and/or speed-dependent. The material for the preform is conveyed with the aid of a press piston or an injection piston.