Means for welding two thermoplastic moldings

The invention relates to a device for welding at least two thermoplastic mold parts with a receptacle for the first thermoplastic molding. It is given a further receptacle for the second thermoplastic molded part, wherein the further receptacle is displaced by means of a vibrating head in vibration to vibration welding of two thermoplastic moldings. The further receptacle comprises a fixing unit which receives a seal bar which extends over a partial area of ​​the area to be welded.