EXTRUDER Russian patent published in 2002 - IPC

FIELD: processing of thermoplastic materials, applicable in branches of industry using extrusion. SUBSTANCE: the extruder has a screw positioned in a body, charging opening, die, successively arranged zones of charging, mixing, pressure stabilization and a predie zone. A screw duct of a variable depth is made on the inner surface of the body. The extruder body is made for rotation and installed on supports. The charging opening is positioned in the plane perpendicular to the axis of rotation of the body and is made jointly with the fixed screw. A double-start thread of a variable depth in the form of tapered ducts expanding towards the die is made on the screw in the zones of mixing and homogenization. The depth of the thread of the duct decreases in proportion with the thread width in the direction from the charging opening to the die. EFFECT: intensified action of compressive forces, eliminated stagnation zones at movement of the processed product in the body duct. 4 dwg