MELT SEALING DEVICE OF EXTRUDER FOR THERMOPLASTIC SYNTHETIC RESIN OR RUBBER

摘要

PURPOSE: To always renew sealing and to avoid the accumulation of a material obstructing operation by forming the melt sealing device of an extruder from a granule supply screw portion, a compression portion having screw thread trough depth, a melt annular passage portion of which the min. length is half the diameter of a screw and a blister portion. CONSTITUTION: A supply screw portion 6 is equipped with a supply bush 3 having a filling opening 5 for a granule or a melt and an insulating bush 4 is provided in the filling opening 5 or the filling opening 5 is regulated in temp. A compression portion 7 having screw thread trough depth becoming shallow in a feed direction and a metering portion 8 having unchangeable screw thread trough depth are provided. A melt annular passage portion 9 which has no screw thread trough and of which the min. length is half the diameter of a screw is provided and, further, a blister portion 10 generating an annular gap 10a for a sealing melt is provided and the screw thread through depth of the metering portion 8 is pref. 1/100.D and the melt annular passage is pref. about 1/10.D.