| 摘要 |
A ring nozzle for use with an extruder to continuously form a synthetic-resin tube has a substantially stationary back nozzle part having an axially forwardly directed front face and formed with an axially centered passage opening at the face. This part is typically bolted over the outlet of the extruder. An axially centered core rod is substantially fixed in the passage and extends axially forward past the front face. This rod is also fixed in the extruder so that same can emit a hot and thick tubular strand of a plastified synthetic resin. An annular and movable front nozzle part fits with spacing around the core forward of the front face and forms therewith an axially centered and forwardly open annular gap. The thick tubular strand formed by the extruder becomes a thin-walled strand that emerges from the annular gap. The axially confronting faces of the front and back mold parts have complementary part-spherical surfaces riding on each other and permitting the front nozzle part to tip limitedly on the back nozzle part, but having adjustment elements braced axially at three or more generally angularly equispaced locations between the back and front faces for tipping the front part on the back part and thereby adjusting the gap. Biasing means urges the front part axially back against the adjustment elements. This biasing means includes springs bearing axially back against the front part. |
