METHOD AND DEVICE FOR BLOWWMOLDING PLASTIC

摘要

The disclosure relates to a method and apparatus for blow moulding hollow plastic articles each having a relatively wide neck portion. The method includes the step of mechanically expanding an end portion of a tubular parison (42) from which the article is to be moulded by means of a "stretcher" mechanism (44). The mechanism (44) includes a plurality of parison engaging elements (52) over which the parison (42) is placed and which are movable radially outwardly to expand the end portion of the parison. A mandrel (46) is then introduced into the expanded end portion (42 min ) of the parison and co-operates with the mould (20, 22) to form the neck of the article. Subsequently, the parison (42) is expanded by internal air pressure to conform to the shape of the mould.