An apparatus for the extrusion of thermofusible materials which are applied while being heated comprises a prefusion and feeding chamber, a heating element for the prefusion and feeding chamber, a shaft capable of rotation at the base of the chamber, the shaft while in rotation mixing the thermofusible material and an extruder comprising an extrusion screw axially connected to said shaft. The extrusion screw is located in a cylindrical tubular structure which is provided with an exit for the thermofusible material. Preferably the shaft is located at a predetermined distance from the bottom wall of the prefusion chamber whereby a passageway is formed between the bottom wall and the shaft, the chamber and the shaft being so dimensioned that the shaft during rotation forces the entire mass of thermofusible material through the passageway. The shaft preferably comprises a first cylindrical portion and a second portion in the form of a helicoidal screw, the diameter of the helicoidal screw being greater than the diameter of the first extrusion screw. According to one embodiment, the apparatus is portable, the prefusion chamber is cylindrical and is provided with a conical base and the shaft is located tangentially to a generatrix of the conical base. The apparatus may be of the gun type. It may be provided with a device for preventing the flow of the material when the apparatus is not in operation.
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