| 摘要 |
Prodn. of constant thickness flat bottles with no pinch-off seam involves extrusion of a parison into a preforming mould, inflation of the parison to form a circular section preform and transfer of the preform, while supporting the base, to a mould with the final dimensions and profile of the flat bottle. A claimed extrusion blowing machine has split preforming and final blowing moulds with an additional moveable tool part for supporting a preform during transfer between the two moulds. Pref. preform support is mechanical and occurs both during preform moulding and mould opening. The additional tool part forms part of the preforming tool, has an upper side corresponding to the preform base and moves vertically. Vertical splitting of the base along the parting plane of the preform tool is advantageous. |
