| 摘要 |
A method and apparatus are disclosed for forming a plastic container by a blow molding operation. In the method, a tubular thermoplastic parison is blown to a preform within a first mold by a blow pipe inserted into one axial open end of the parison. Prior to removing the preform from the first mold, a secondary opening is formed in the wall of the preform, either by a spike-shaped piercing surface over which the parison is expanded or by a vent port through which blow air is exhausted to rupture an opening in the preform wall. The preform is then transferred to a second mold, which pinches shut the initial blowing opening of the preform. A second blow pin is inserted into the secondary opening to supply blow air under pressure to expand the preform to a container. The secondary opening may be formed into a finish opening on the container during the second blow molding operation, thus enabling the finish opening to be located at a position remote from the position on the container which corresponds to an axial extremity on the original tubular parison.
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