Method of blow molding
US4126658A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 28, 1977 |
| Grant date | Nov 21, 1978 |
| Priority date | — |
| Expiry date | Oct 28, 1997 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C49/76
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
An improved method of blow molding bottles of thermoplastic material wherein intermittent extrusion apparatus is employed to produce bottles with finished necks free of external blemishes, the method including the steps of intermittently extruding tubular parisons from an annular orifice, enclosing the first tubular parison in a mold that has an interior cavity that defines the bottle and also defines a dome radiating outward from the upper end of the bottle neck, immediately blowing the parison essentially to the shape of the cavity, but as an incident to the blowing of the parison and to the interruption of the extrusion, causing the thermoplastic material to be severed at the extrusion orifice, and immediately shifting the mold enclosed article to a shaping station while the article is still at a temperature sufficient for subsequent shaping operations, and at the shaping station finish blowing the article while trimming and at least partially compression-molding the neck.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.