SINGLE SCREW EXTRUDER OR TWIN SCREW EXTRUDER FOR FEEDING POWDERED OR FIBROUS ADDITIVE TO THERMOPLASTIC MOLTEN BODY

摘要

PURPOSE: To obtain a good homogenous product by providing a disc having a contour element effective to be sent to the back thereof and having an outer diameter almost corresponding to the inner diameter of a casing and a spacer disc having a diameter corresponding to the trough diameter of a screw in an almost injection region. CONSTITUTION: An oblique tooth form effective for sending the back parts 8 of discs 5 presses a melt and powdery addives to the intermediate spaces 16-22 between two discs and these intermediate spaces are formed by spacer discs 27 set to a smaller dimension in diameter. These spacer discs 27 have a diameter almost corresponding to the trough diameter of screws 11, 12 in the injection regions of the screws. The trough diameter of both screws are generally made equal over the total screw length in a twin-screw extruder. The powdery or fibrous additives are supplied to a second injection port 4. The instantaneous supply of a material is performed but surprisingly good mixing is developed at the same time.