Extrusion head for an extrusion installation of the rubber or plastic processing industry

摘要

An extrusion head for an extrusion installation for extruding plastic material and having two, three or four extrusion cylinders has a stationary part which is fixedly mounted on the discharge ends of the extrusion cylinders and has flow channels for directing extrudate leading from the cylinders to a central extrusion location at which there is a seat for an extrusion die. Two movable extrusion head parts are hinged on the stationary part for movement between a closed position in which the movable extrusion head parts define an extrusion orifice for the extrudate and hold the extrusion die on its seat and an open position for cleaning. The movable extrusion head parts are moved between open and closed position by piston-cylinder units having cylinders pivotally mounted on the stationary part and having piston rods pivotally connected to lugs on the movable extrusion head parts. Other piston-cylinder units having cylinders mounted on the stationary extrusion head part have piston rods formed as draw bars on which are pivotally mounted tie rods actuated by further piston-cylinder units and having head portions engaging the respective movable extrusion head parts to press them into closed position. An electric-hydraulic system controlled by a central programmed control unit supplies hydraulic fluid to the piston-cylinder units to activate them in predetermined sequence for the opening and the closing of the extrusion head.