ABSTRACT
A food extruder consists of a flighted Archimedes screw which rotates in a tightly fitting cylindrical barrel. The frame positions the working members of the extruder so that they can function easily, and supports the major extruder components including feeders, screw, barrel, and drive. A bearing is required to support and center the extrusion screw and absorb the thrust exerted by the screw. In certain instances, an assembly can be attached directly to the discharge of the extruder which contains an adjustable discharge valve. Individual feeders on each stream control the rate of addition of the various ingredient types to a continuous blender before they enter the extruder. Variation of the screw speed on the extruder is a valuable control parameter. A transmission is used to reduce the speed with a proportional increase in the torque of the drive motor. The food ingredients are normally heated and worked into a continuous dough mass during passage through the transition section.
