Method for moulding an article from plastic material
US4409176A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 14, 1980 |
| Grant date | Oct 11, 1983 |
| Priority date | — |
| Expiry date | Oct 14, 2000 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2031/772
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
An article (11) of thermoplastic material is moulded from a parison (10) in which certain parts (17,16) of the parison are re-formed while other parts (13,12,20) retain their shape. A difference in pressure is applied to the wall of the parison during the re-forming process. Material in the parison is also moved in the direction of those parts of the parison which are to be re-formed, whereby attenuation of the material may be avoided entirely, if so desired, also in those parts which are to be re-formed. The invention enables the parison for a bottle to be re-formed to an extent which is small by comparison with the thickness of the material, for example the so-called "neck support" ring and the so-called "pilfer proof" ring, starting with a tube of oriented material. In a device for the application of the invention the elements (22,21,25) are in contact with the parts (13,12,20) of the parison. Between the elements, which are movable relative to each other, are to be found depressions (27,26) in which the parts (17,16) are re-formed. When the elements (22,21,25) are moved towards each other, the size of the depressions is reduced in the direction of the movement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.