Parison stretcher
US4518558A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 7, 1983 |
| Grant date | May 21, 1985 |
| Priority date | — |
| Expiry date | Mar 7, 2003 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C49/761
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A method and apparatus for producing hollow plastic articles are disclosed. The articles have a blow-molded portion and a compression-molded portion, and are formed by downwardly extruding plastic at at least one extrusion rate to progressively form a parison having a downwardly facing open end from a first location adjacent an extrusion head toward a second location axially spaced therefrom. A male mold member is provided at the second location. Portions of the open end of the parison are engaged by a plurality of fingers, while the open end travels toward the second location and the engaged portions are moved downwardly at a rate at least corresponding to the extrusion rate. During the travel toward the second location, portions of the open end are radially expanded and guided over the male mold member. The parison is enclosed in a hollow mold having a molding surface corresponding to the blow-molded portion of the hollow article and having a second portion having a molding surface corresponding to the compression molded portion of the hollow article and cooperating with the male mold member. Air is admitted to the interior of the first portion to form the blow-molded portion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.