Patent ID: 6286988
Filing Date: 2001-09-11
Classification: B29C

Abstract:
An extrusion head for attachment to a conveying device, the conveying device including an extruder, or other extrusion device, the extrusion head being a mixing device and providing an adjustable shear effect, said extrusion head plasticizing, homogenizing, mixing and shearing of material conveyed to it, the material being in the form of polyester melts, elastomers and their miscible and past materials, said extrusion head comprising: first and second toothed wheels arranged one over the other, said first of said toothed wheels having teeth separated from each other by tooth gaps on the exterior surface thereof and said second of said toothed wheels having axially spaced teeth separated from each other by tooth gaps with an annular groove between said spaced teeth, said teeth having an inclined geometry configured to urge the material being fed between the tooth gaps toward the axial center of the toothed wheels for shearing the material and for mixing with new material being fed by the conveying device, and to move the crushed material toward the center of said toothed wheels into the newly arriving material and into said annular groove; a housing for said toothed wheels having an outlet channel; and means for controlling the speed of said toothed wheels for discharging some of the processed material and for supplying a portion of the material back into a material flow from the conveying device according to the speed of one of said toothed wheels.