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Extruder

The new extruder contains two significant developments: the first is the temperating unit for the elimination of the homogeniety problems and the second is the compact gear designed specially for extruder driving.
In the cylindric mantle of the temperating unit we placed infra red ceramic heaters at a given distance from the surface of the screw. We built it together with a ventillator blowing cooling air in a tangential direction between the screw-house and the ceramic heaters. This cooling air passes through the temperating unit on a spiral lane then it leaves the system. Similarly to the heating zones of the traditional extruders there are more temperating units installed on the screw-house. The infra red units heat only forward in contrast with the traditional mantle heating which heats backwards as well. With this new system the all electrical energy consumed will be transferred to the screw and therefore indirectly into the material. There is a given distance between the ceramic heaters and the surface of the screw, where we can blow the cooling air in. We eliminated the insulating effect of the heaters. The cooling air is blown in tangentially instead of a certain point of the screw. This way the cooling air goes around the mantle completely and many times, assuring uniform cooling everywhere. This method allowed us to reach a total temperature homogeniety of the cross-section. With the alteration of the heating the local cold and hot spots were eliminated, the homogeniety of the mantle’s thermocarthogramm has improved and the temperature difference between the under and upper parts of the screw-house disappeared. Therefore we eliminated the bending of the screw-house and the associated wears.

We have also replaced the commonly applied belt extruder gear with a totally new solution. The new linear planetary gear has been specially designed for extruders. This gear does not contain any average or universal element, it was designed for the stresses generated by the extrusion. It also includes the axial bearings taking up the axle-direction load from the screw. The linear arrangement means the gear motor is situated at the same axle as the extruder screw. This method also eliminates the additional bending stress occuring in traditional solutions. The forceline of the planetary gear ends up on the house of the gear and therefore other elements are relieved from stress. The serial arrangement allows very small space requirement. Owing to the compact construction it is enough to support only one unit to get a stable hold for the whole system. Based on the above we can state that this gear is really an extruder gear.