| 摘要 |
The external part of an extrusion channel (12') is surrounded by a heat-storage member (26) maintained at a temperature above the softening point of the thermoplastic material to be extruded. This storage member (26) constitutes a heat source from which each individual extrusion channel can be heated above the range of softening temperatures of the polymer, so as to assist the melting of the solidified block of polymer which could sometimes obstruct this channel. An air space (29) is used to slow down the heat transfer from the storage member (26) to the individual extrusion channels (12') in order to allow savings in heat whilst still maintaining the high temperature source available for melting solidified plugs. <IMAGE>
|
