Mouthpiece discriminating device for rotary roll extruder.

摘要

A mouthpiece discriminating device for a rotary roll extruder serves to distinguish different kinds of exchangeable mouthpieces (18) from one another without relying upon visual inspection. The device includes a plurality of magnets (38a-38e) embedded in the mouthpiece along its edge and aligned with each other in a direction of passage for the mouthpiece. The poles of the magnets are arranged as coded information uniquely determined in accordance with kind of the mouthpiece. A detector element (40) provided along the passage detects the magnetic fields of the magnets upon movement of the mouthpiece along the passage. A signal processing unit (46) discriminating the kind of the mouthpiece based on output signals of the detector element representing the magnetic fields detected.